0001547903-22-000060 | 10-K | XBRL Viewer

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CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Assets
Fixed maturities, available-for-sale, at fair value (amortized cost of $2,078,773 and $1,730,835 as of December 31, 2021 and December 31, 2020, respectively)	$ 2,085,931	$ 1,804,286
Cash and cash equivalents (including restricted cash of $3,165 and $5,555 as of December 31, 2021 and December 31, 2020, respectively)	76,646	126,937
Premiums receivable	60,358	49,779
Accrued investment income	11,900	9,862
Prepaid expenses	3,530	3,292
Deferred policy acquisition costs, net	59,584	62,225
Software and equipment, net	32,047	29,665
Intangible assets and goodwill	3,634	3,634
Prepaid reinsurance premiums	2,393	6,190
Reinsurance recoverable	20,320	17,608
Other assets	94,238	53,188
Total assets	2,450,581	2,166,666
Liabilities
Debt	394,623	393,301
Unearned premiums	139,237	118,817
Accounts payable and accrued expenses	72,000	61,716
Reserve for insurance claims and claim expenses	103,551	90,567
Reinsurance funds withheld	5,601	8,653
Warrant liability, at fair value	2,363	4,409
Deferred tax liability, net	164,175	112,586
Other liabilities	3,245	7,026
Total liabilities	884,795	797,075
Commitments and contingencies
Shareholders' equity
Common stock - class A shares, $0.01 par value; 85,792,849 and 85,163,039 shares issued and outstanding as of December 31, 2021 and December 31, 2020, respectively (250,000,000 shares authorized)	858	852
Additional paid-in capital	955,302	937,872
Accumulated other comprehensive income, net of tax	1,485	53,856
Retained earnings	608,141	377,011
Total shareholders' equity	1,565,786	1,369,591
Total liabilities and shareholders' equity	$ 2,450,581	$ 2,166,666

CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Statement of Financial Position [Abstract]
Amortized Cost	$ 2,078,773	$ 1,730,835
Restricted cash	$ 3,165	$ 5,555
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, issued (in shares)	85,792,849	85,163,039
Common stock, outstanding (in shares)	85,792,849	85,163,039
Common stock, authorized (in shares)	250,000,000	250,000,000

CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME - USD ($) shares in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Revenues
Net premiums earned	$ 113,933,000	$ 113,594,000	$ 110,888,000	$ 105,879,000	$ 100,709,000	$ 98,802,000	$ 98,944,000	$ 98,717,000	$ 444,294,000	$ 397,172,000	$ 345,015,000
Net investment income	10,045,000	9,831,000	9,382,000	8,814,000	8,386,000	8,337,000	7,070,000	8,104,000	38,072,000	31,897,000	30,856,000
Net realized investment gains	714,000	3,000	12,000	0	295,000	(4,000)	711,000	(72,000)	729,000	930,000	45,000
Other revenues	380,000	613,000	483,000	501,000	513,000	648,000	1,223,000	900,000	1,977,000	3,284,000	2,855,000
Total revenues									485,072,000	433,283,000	378,771,000
Expenses
Insurance claims and claim expenses	(500,000)	3,204,000	4,640,000	4,962,000	3,549,000	15,667,000	34,334,000	5,697,000	12,305,000	59,247,000	12,507,000
Underwriting and operating expenses	38,843,000	34,669,000	34,725,000	34,065,000	34,994,000	33,969,000	30,370,000	32,277,000	142,303,000	131,610,000	126,621,000
Service expenses	650,000	787,000	481,000	591,000	459,000	557,000	1,090,000	734,000	2,509,000	2,840,000	2,248,000
Interest expense	8,029,000	7,930,000	7,922,000	7,915,000	7,906,000	7,796,000	5,941,000	2,744,000	31,796,000	24,387,000	12,085,000
(Gain) loss from change in fair value of warrant liability	(112,000)	0	(658,000)	205,000	1,379,000	437,000	1,236,000	(5,959,000)		(2,907,000)	8,657,000
(Gain) loss from change in fair value of warrant liability									(566,000)	(2,907,000)	0
Total expenses									188,347,000	215,177,000	162,118,000
Income before income taxes	78,162,000	77,451,000	73,655,000	67,456,000	61,616,000	49,357,000	34,977,000	72,156,000	296,725,000	218,106,000	216,653,000
Income tax expense	17,639,000	17,258,000	16,133,000	14,565,000	13,348,000	11,178,000	8,129,000	13,885,000	65,595,000	46,540,000	44,696,000
Net income	$ 60,523,000	$ 60,193,000	$ 57,522,000	$ 52,891,000	$ 48,268,000	$ 38,179,000	$ 26,848,000	$ 58,271,000	$ 231,130,000	$ 171,566,000	$ 171,957,000
Earnings per share
Basic (in dollars per share)	$ 0.71	$ 0.70	$ 0.67	$ 0.62	$ 0.57	$ 0.45	$ 0.36	$ 0.85	$ 2.70	$ 2.20	$ 2.54
Diluted (in dollars per share)	$ 0.69	$ 0.69	$ 0.65	$ 0.61	$ 0.56	$ 0.45	$ 0.36	$ 0.74	$ 2.65	$ 2.13	$ 2.47
Weighted average common shares outstanding
Basic (in shares)	85,757	85,721	85,647	85,317	84,956	84,805	73,617	68,563	85,620	78,023	67,573
Diluted (in shares)	87,117	86,880	86,819	86,487	86,250	85,599	74,174	70,401	86,885	79,263	69,721
Other comprehensive (loss) income, net of tax:
Unrealized (losses) gains in accumulated other comprehensive income, net of tax (benefit) expense of $(13,768), $9,525 and $8,548 for each of the years in the three-year period ended December 31, 2021, respectively									$ (51,795,000)	$ 35,829,000	$ 32,155,000
Reclassification adjustment for realized (gains) losses included in net income, net of tax expense (benefit) of $153, $(196) and $9 for each of the years in the three-years ended December 31, 2021, respectively									(576,000)	739,000	(35,000)
Other comprehensive (loss) income, net of tax									(52,371,000)	36,568,000	32,120,000
Comprehensive income									$ 178,759,000	$ 208,134,000	$ 204,077,000

CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME (Parenthetical) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Statement of Comprehensive Income [Abstract]
Net unrealized (losses) gains in accumulated other comprehensive income, tax (benefit) expense									$ (13,768)	$ 9,525	$ 8,548
Reclassification adjustment for realized losses (gains) included in net income, tax expense (benefit)									$ 153	(196)	9
(Gain) loss from change in fair value of warrant liability	$ (112)	$ 0	$ (658)	$ 205	$ 1,379	$ 437	$ 1,236	$ (5,959)		$ (2,907)	$ 8,657

CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common Stock - Class A	Additional Paid-in Capital	Accumulated Other Comprehensive Income (Loss)	Retained Earnings
Beginning balance (in shares) at Dec. 31, 2018		66,319,000
Beginning balance at Dec. 31, 2018	$ 701,500	$ 663	$ 682,181	$ (14,832)	$ 33,488
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock: class A shares issued related to warrant exercises (in shares)		289,000
Common stock: class A shares issued related to warrant exercises	8,312	$ 3	8,309
Common stock: class A shares issued under stock plans, net of shares withheld for employee taxes (in shares)		1,750,000
Common stock: class A shares issued under stock plans, net of shares withheld for employee taxes	3,500	$ 18	3,482
Share-based compensation expense	13,031		13,031
Change in unrealized investment gains/losses, net of tax expense	32,120			32,120
Net income	171,957				171,957
Ending balance (in shares) at Dec. 31, 2019		68,358,000
Ending balance at Dec. 31, 2019	$ 930,420	$ 684	707,003	17,288	205,445
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock: class A shares issued related to warrant exercises (in shares)	11,000	11,368
Common stock: class A shares issued related to warrant exercises	$ 325		325
Common stock: class A shares issued related to public offering (in shares)		15,870,000
Common stock: class A shares issued related to public offering	219,687	$ 159	219,528
Common stock: class A shares issued under stock plans, net of shares withheld for employee taxes (in shares)		924,000
Common stock: class A shares issued under stock plans, net of shares withheld for employee taxes	(90)	$ 9	(99)
Share-based compensation expense	11,115		11,115
Change in unrealized investment gains/losses, net of tax expense	36,568			36,568
Net income	171,566				171,566
Ending balance (in shares) at Dec. 31, 2020		85,163,000
Ending balance at Dec. 31, 2020	$ 1,369,591	$ 852	937,872	53,856	377,011
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock: class A shares issued related to warrant exercises (in shares)	86,000	86,000
Common stock: class A shares issued related to warrant exercises	$ 1,983	$ 1	1,982
Common stock: class A shares issued under stock plans, net of shares withheld for employee taxes (in shares)		544,000
Common stock: class A shares issued under stock plans, net of shares withheld for employee taxes	(1,225)	$ 5	(1,230)
Share-based compensation expense	16,678		16,678
Change in unrealized investment gains/losses, net of tax expense	(52,371)			(52,371)
Net income	231,130				231,130
Ending balance (in shares) at Dec. 31, 2021		85,793,000
Ending balance at Dec. 31, 2021	$ 1,565,786	$ 858	$ 955,302	$ 1,485	$ 608,141

CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Change in unrealized investment gains/losses, tax expense (benefit)	$ 13,921	$ 9,721	$ 8,539
Common stock: class A shares issued related to warrant exercises (in shares)	86,000	11,000
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common Stock - Class A
Common stock: class A shares issued related to warrant exercises (in shares)	86,000	11,368	289,000

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Cash flows from operating activities
Net income	$ 231,130	$ 171,566	$ 171,957
Adjustments to reconcile net income to net cash provided by operating activities:
Net realized investment gains	(729)	(930)	(45)
(Gain) loss from change in fair value of warrant liability	(566)	(2,907)	8,657
Depreciation and amortization	11,232	9,930	9,299
Net amortization of premium on investment securities	6,733	3,668	1,252
Amortization of debt discount and debt issuance costs	1,861	4,036	1,011
Deferred income taxes	65,510	46,506	45,082
Share-based compensation expense	16,678	11,115	13,031
Changes in operating assets and liabilities:
Premiums receivable	(10,579)	(3,694)	(10,078)
Accrued investment income	(2,038)	(3,031)	(1,137)
Prepaid expenses	(238)	220	(472)
Deferred policy acquisition costs, net	2,641	(2,253)	(13,132)
Reinsurance recoverable	(2,712)	(12,669)	(1,939)
Other assets	(42,833)	(38,804)	(8,831)
Unearned premiums	20,420	(17,825)	(22,251)
Reserve for insurance claims and claim expenses	12,984	66,815	10,941
Reinsurance balances, net	(683)	2,783	917
Accounts payable and accrued expenses	16,908	18,072	3,888
Net cash provided by operating activities	325,719	252,598	208,150
Cash flows from investing activities
Purchase of short-term investments	(10,640)	(42,241)	(230,362)
Purchase of fixed-maturity investments, available-for-sale	(514,405)	(1,065,916)	(290,533)
Proceeds from maturity of short-term investments	0	86,045	244,921
Proceeds from redemptions, maturities and sale of fixed-maturity investments, available-for-sale	163,103	404,717	91,575
Software and equipment	(12,238)	(12,159)	(9,956)
Net cash used in investing activities	(374,180)	(629,554)	(194,355)
Cash flows from financing activities
Proceeds from issuance of common stock related to public offering, net of issuance costs	0	219,687	0
Proceeds from issuance of common stock related to employee equity plans	4,201	8,871	21,748
Proceeds from issuance of common stock related to warrant exercises	503	0	0
Taxes paid related to net share settlement of equity awards	(5,426)	(8,961)	(18,248)
Proceeds from senior secured notes	0	400,000	0
Repayments of term loan	0	(147,750)	(1,500)
Payments of debt issuance costs	(1,108)	(9,043)	0
Net cash (used in) provided by financing activities	(1,830)	462,804	2,000
Net (decrease) increase in cash, cash equivalents and restricted cash	(50,291)	85,848	15,795
Cash, cash equivalents and restricted cash, beginning of period	126,937	41,089	25,294
Cash, cash equivalents and restricted cash, end of period	76,646	126,937	41,089
Supplemental disclosures of cash flow information
Interest paid	29,500	17,561	10,691
Income taxes refunded	$ 457	$ 70	$ 64

Organization and Basis of Presentation	12 Months Ended
Organization and Basis of Presentation	Dec. 31, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Basis of Presentation	Organization and Basis of Presentation NMI Holdings, Inc. (NMIH) is a Delaware corporation, incorporated in May 2011 to provide private mortgage guaranty insurance (which we refer to as mortgage insurance or MI) through its wholly-owned insurance subsidiaries, National Mortgage Insurance Corporation (NMIC) and National Mortgage Reinsurance Inc One (Re One). Our common stock is listed on the NASDAQ exchange under the ticker symbol "NMIH." NMIC, our primary insurance subsidiary, issued its first mortgage insurance policy in April 2013. NMIC is licensed to write mortgage insurance in all 50 states and the District of Columbia (D.C.). Re One historically provided reinsurance coverage to NMIC in accordance with certain statutory risk retention requirements. Such requirements have been repealed and the reinsurance coverage provided by Re One to NMIC has been commuted. Re One remains a wholly-owned, licensed insurance subsidiary; however, it does not currently have active insurance exposures. In August 2015, NMIH capitalized a wholly-owned subsidiary, NMI Services, Inc. (NMIS), through which we offer outsourced loan review services to mortgage loan originators. Basis of Presentation The accompanying consolidated financial statements include the results of NMIH and its wholly-owned subsidiaries. All inter-company transactions have been eliminated. These financial statements have been prepared in accordance with accounting principles generally accepted in the U.S. (GAAP) and our accounts are maintained in US dollars. The preparation of financial statements in accordance with GAAP requires management to make estimates and assumptions that affect reported amounts of assets and liabilities, as well as disclosure of contingent assets and liabilities as of the balance sheet date. Estimates also affect the reported amounts of income and expenses for the reporting period. Actual results could differ from those estimates. COVID-19 Developments On January 30, 2020, the World Health Organization (WHO) declared the outbreak of COVID-19 a global health emergency and subsequently characterized the outbreak as a global pandemic on March 11, 2020. In an effort to stem contagion and control the COVID-19 pandemic, the population at large severely curtailed day-to-day activity and local, state and federal regulators imposed a broad set of restrictions on personal and business conduct nationwide. The COVID-19 pandemic, along with the widespread public and regulatory response, caused a dramatic slowdown in U.S. and global economic activity and a record number of Americans were furloughed or laid-off in the ensuing downturn. The global dislocation caused by COVID-19 was unprecedented. In response to the COVID-19 outbreak and uncertainty that it introduced, we activated our disaster continuity program to ensure our employees were safe and able to manage our business without interruption. We pursued a broad series of capital and reinsurance transactions to bolster our balance sheet and expand our ability to serve our customers and their borrowers, and we updated our underwriting guidelines and policy pricing in consideration of the increased level of macroeconomic volatility. While the acute economic impact of COVID-19 has begun to recede, the pandemic continues to affect communities across the U.S. and poses significant risk globally. The path and pace of global economic recovery will depend, in large part, on the course of the virus, which itself remains unknown and subject to risk. Given this uncertainty, we are not able to fully assess or estimate the ultimate impact COVID-19 will have on the mortgage insurance market, our business performance or our financial position including our new business production, default and claims experience, and investment portfolio results at this time. CEO Transition On September 9, 2021, we announced that Adam Pollitzer, then the company’s Executive Vice President and Chief Financial Officer, was appointed as the company's President and Chief Executive Officer, effective January 1, 2022. Mr. Pollitzer also joined the company’s Board of Directors upon assuming his new role. He succeeded Claudia Merkle, who stepped down as Chief Executive Officer and as a member of the Board, effective December 31, 2021. We recorded $3.8 million of severance, restricted stock modification and other expenses related to this transition during the year ended December 31, 2021.

Summary of Accounting Principles	12 Months Ended
Summary of Accounting Principles	Dec. 31, 2021
Accounting Policies [Abstract]
Summary of Accounting Principles	Summary of Accounting Principles Use of Estimates We use accounting principles and methods that conform to GAAP. We are required to apply significant judgment and make material estimates in the preparation of our financial statements and with regard to various accounting, reporting and disclosure matters. Assumptions and estimates are required to apply these principles where actual measurement is not possible or practical. Insurance Premium Revenue Recognition Premiums for primary mortgage insurance policies may be paid in a single payment at origination (single premium), on a monthly installment basis (monthly premium) or on an annual installment basis (annual premium), with such election and payment type fixed at policy inception. Premiums written at origination for single premium policies are initially deferred as unearned premiums and amortized into earnings over the estimated policy life, in accordance with the anticipated expiration of risk. Monthly premiums are recognized as revenue in the month billed and when the coverage is effective. Annual premiums are initially deferred and earned on a straight-line basis over the year of coverage. Upon cancellation of a policy, all remaining non-refundable deferred and unearned premium is immediately earned, and any refundable deferred and unearned premium is returned to the policyholder and recorded as a reduction to written premium and unearned premium reserve in the period paid. Premiums written on pool transactions are earned over the period that coverage is provided. Concentrations For the years ended December 31, 2021, 2020 and 2019 no customer accounted for more than 10% of our consolidated revenues. At December 31, 2021, December 31, 2020 and December 31, 2019 approximately 10%, 11% and 12% of our total risk-in-force (RIF) was concentrated in California. Reserves for Insurance Claims and Claim Expenses We establish reserves for claims based on our best estimate of the ultimate claim costs for defaulted loans using the general principles contained in ASC 944, Financial Services - Insurance (ASC 944). A loan is considered to be in "default" as of the payment date at which a borrower has missed the preceding two or more consecutive monthly payments. We establish reserves for loans that have been reported to us in default by servicers, referred to as case reserves, and additional loans that we estimate (based on actuarial review and other factors) to be in default that have not yet been reported to us by servicers, referred to as incurred but not reported (IBNR) reserves. We also establish reserves for claim expenses, which represent the estimated cost of the claim administration process, including legal and other fees, as well as other general expenses of administering the claim settlement process. Claim expense reserves are either allocated (i.e., associated with a specific claim) or unallocated (i.e., not associated with a specific claim). The establishment of claims and claim expense reserves is subject to inherent uncertainty and requires significant judgment by management. Reserves are established by estimating the number of loans in default that will result in a claim payment, which is referred to as claim frequency, and the amount of claim payment expected to be paid on each such loan in default, which is referred to as claim severity. Claim frequency and severity estimates are established based on historical observed experience regarding certain loan factors, such as age of the default, size of the loan and loan-to-value (LTV) ratios, and are strongly influenced by assumptions about the path of certain economic factors, such as house price appreciation, trends in unemployment and mortgage rates. We consider the appropriateness of such inputs at each fiscal quarter and conduct an actuarial review annually to evaluate and, if necessary, update these assumptions. Investments We have designated our investment portfolio as available-for-sale and report our invested assets at fair value. Unrealized gains and losses in the portfolio, net of related tax expense or benefit, are recognized as a component of accumulated other comprehensive income (AOCI) in shareholders' equity. We measure fair value and classify invested assets in a hierarchy for disclosure purposes consisting of three "levels" based on the observability of inputs available in the marketplace used to measure fair value. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets (Level 1 measurements) and the lowest priority to unobservable inputs (Level 3 measurements). See Note 4, "Fair Value of Financial Instruments" for further discussion. Purchases and sales of investments are recorded on a trade date basis. Net investment income is recognized when earned, and includes interest and dividend income together with amortization of market premiums and discounts using the effective yield method, and is net of investment management fees and other investment related expenses. For asset-backed securities and any other holdings for which there is a prepayment risk, prepayment assumptions are evaluated and revised as necessary. Any adjustments required due to changes in effective yields and prepayment assumptions are recognized on a prospective basis. We recognize an impairment on a security through the consolidated statement of operations and comprehensive income if (i) we intend to sell the impaired security; or (ii) it is more likely than not that we will be required to sell the impaired security prior to recovery of its amortized cost basis. If a sale is intended or likely to be required, we write down the amortized cost basis of the security to fair value and recognize the full amount of the impairment through the statement of operations as a "Realized Investment Loss." For securities in an unrealized loss position where a sale is not intended or likely to be required, we further assess if the decline in fair value below amortized cost is driven by a credit related impairment, considering several items including, but not limited to: •the severity of the decline in fair value; •the financial condition of the issuer; •the failure of the issuer to make scheduled interest or principal payments; •recent rating downgrades of the applicable security or issuer by one or more nationally recognized statistical ratings organization; and •other adverse conditions related to or impacting the security or issuer. To the extent we determine that a security impairment is credit-related, an impairment loss is recognized through the statement of operations as a provision for credit loss expense, and presented as a "Realized Investment Loss." We recognize an allowance for credit losses for the difference between the amortized cost and present value of future expected cash flows, limited by the amount the fair value of the security is below its amortized cost. Subsequent changes (favorable and unfavorable) in credit losses are recognized through the statement of operations as a provision for or a reversal of credit loss expense, and presented as a "Realized Investment Gain or Loss." The portion of a security impairment attributed to other non-credit related factors is recognized in other comprehensive income, net of taxes. We have elected to present accrued interest receivable separately from available for sale securities on our consolidated balance sheet. Accrued interest receivable was $11.9 million as of December 31, 2021 and is included in "Accrued Investment Income." We have elected not to measure an allowance for credit losses for accrued interest receivable on available for sale securities. Accrued interest for available for sale securities is written off against interest income when the receivable has aged 90 days past due. We did not write off any accrued interest receivable during the years ended December 31, 2021, 2020 or 2019. We consider items such as commercial paper with original maturities of 90 days or less to be short-term investments. Deferred Policy Acquisition Costs (DAC) Costs directly associated with the successful acquisition of mortgage insurance policies, consisting of certain selling expenses and other policy issuance and underwriting expenses, are initially deferred and reported as DAC. DAC is reviewed periodically to determine that it does not exceed recoverable amounts. DAC is amortized to expense in proportion to estimated gross profits over the life of the associated policies. We revise the rate of amortization to reflect actual experience and any changes to persistency or loss development. Total amortization of DAC for the years ended December 31, 2021, 2020 and 2019, net of a portion of the ceding commissions earned under our quota share reinsurance agreements (see "Reinsurance", below), was $22.8 million, $19.1 million and $8.4 million, respectively. Premium Deficiency Reserves We consider whether a premium deficiency exists and premium deficiency reserve is required at each fiscal quarter using best estimate assumptions as of the testing date. Per ASC 944, a premium deficiency reserve shall be recognized if the sum of expected claim costs and claim adjustment expenses, expected dividends to policyholders, unamortized acquisition costs and maintenance costs exceeds future premiums, existing reserves and anticipated investment income. We have determined that no premium deficiency reserves were necessary for any of the years in the three-year period ended December 31, 2021. Reinsurance We account for premiums, claims and claim expenses that are ceded to reinsurers on basis consistent with that which we use to account for the original policies we issue and pursuant to the terms of our reinsurance contracts. We account for premiums ceded or otherwise paid to reinsurers as a reduction to premium revenue. NMIC entered into quota share reinsurance treaties effective September 1, 2016 (the 2016 QSR Transaction), January 1, 2018 (the 2018 QSR Transaction), April 1, 2020 (the 2020 QSR Transaction), January 1, 2021 (the 2021 QSR Transaction), October 1, 2021 (the 2022 QSR Transaction), and effective January 1, 2023 (the 2023 QSR Transaction), which we refer to collectively as the QSR Transactions. We earn profit and ceding commissions in connection with the QSR Transactions (see Note 6, "Reinsurance"). Profit commissions represent a percentage of the profits recognized by reinsurers that are returned to us, based on the level of claims and claim expenses that we cede. We recognize any profit commissions we earn as an increase to premium revenue. Ceding commissions are calculated as a percentage of ceded written premiums under the 2016 QSR Transaction and as a percentage of ceded earned premiums under the 2018, 2020, 2021, 2022, and 2023 QSR Transactions, and are intended to cover our costs of acquiring and servicing direct policies. We recognize any ceding commissions generated under the QSR Transactions in a manner consistent with our recognition of earnings on the underlying reinsured policies. We account for ceding commissions earned as a reduction to underwriting and operating expenses. Under the QSR Transactions, we cede a portion of claims and claim expenses and reserves to our reinsurers, and account for such ceded reserves as "Reinsurance Recoverables" on the consolidated balance sheets and such ceded expenses as reductions to claims and claim expenses on the consolidated statements of operations. As of December 31, 2021, we had $20.3 million of reinsurance recoverables under the QSR Transactions. We remain directly liable for all claim payments if we are unable to collect the recoverables due from our reinsurers and, as such, we actively monitor and manage our counterparty credit exposure to our reinsurance providers. We establish an allowance for expected credit loss against our reinsurance recoverables if we do not expect to recover amounts due from one or more of our reinsurance counterparties, and report our reinsurance recoverables net of such allowance, if any. We actively monitor the counterparty credit profiles of our reinsurers and each is required to partially collateralize its obligations under the terms of our QSR Transactions. The allowance for credit loss established with respect to our reinsurance recoverables was deemed immaterial as of December 31, 2021 and 2020. Income Taxes We account for income taxes using the liability method in accordance with ASC Topic 740, Income Taxes. The liability method measures the expected future tax effects of temporary differences at the enacted tax rates applicable for the period in which the deferred asset or liability is expected to be realized or settled. Temporary differences are differences between the tax basis of an asset or liability and its reported amount in the consolidated financial statements that would result in future increases or decreases in taxes owed on a cash basis compared to amounts already recognized as tax expense in the consolidated statement of operations. Warrants We account for warrants to purchase our common shares in accordance with ASC 470-20, Debt with Conversion and Other Options and ASC 815-40 Derivatives and Hedging - Contracts in Entity's Own Equity. Our outstanding warrants may be settled through either (i) physical settlement method, or (ii) cashless exercise, where the number of shares issued upon exercise of the warrants is reduced to cover the cost of the exercise in lieu of the holder remitting a cash payment for the exercise price. The warrants expire and are not exercisable after the 10th anniversary of the date issued. The number of warrants and exercise price are subject to anti-dilution provisions whereby the number of warrants may be increased and their exercise price may be adjusted downward under certain circumstances. The anti-dilutive adjustments may be in excess of any dilution incurred by the warrant holders, and may be triggered by events that are not dilutive. As a result, the warrants are classified as a liability. We revalue the warrants at the end of each reporting period, and any change in fair value is reported in the statements of operations in the period in which the change occurred. We calculated the fair value of the warrants using a Black-Scholes option-pricing model in combination with a binomial model. Share-Based Compensation We account for stock compensation in accordance with ASC 718, Compensation - Stock Compensation, which addresses accounting for share-based awards and recognition of compensation expense, measured using grant date fair value, over the requisite service or performance period of the award. Share-based compensation includes restricted stock units (RSUs) and stock option grants under our Stock Plans. We calculate the fair value of stock option grants using a Black-Scholes option pricing model, which takes into account various subjective assumptions. Key assumptions used in the model include the expected volatility of our stock price, dividend yield and the risk-free interest rate, as well as the expected option term, giving consideration to the contractual terms of any award. RSU grants may contain a service condition, or performance and service conditions. RSU grants are valued at our stock price on the date of grant less the present value of anticipated dividends. We account for stock option and RSU forfeitures as they occur. Earnings per Share (EPS) Basic earnings (loss) per share is based on the weighted-average number of common shares outstanding. Diluted earnings (loss) per share is based on the weighted-average number of common shares outstanding and common share equivalents that would be issuable upon the vesting of existing service based and certain performance and service based RSUs, and exercise of vested and unvested stock options and outstanding warrants. Cash and Cash Equivalents We consider items such as certificates of deposit and money market funds with original maturities of 90 days or less to be cash equivalents. Software and Equipment We capitalize certain costs associated with the development of internal-use software and equipment. Software and equipment are stated at cost, less accumulated amortization and depreciation. Amortization of software and depreciation of equipment commences at the beginning of the month following our placement of the assets into use. Amortization and depreciation are calculated on a straight-line basis over the estimated useful life of the respective assets, typically from three to five years, unless factors indicate a shorter useful life. For further detail, see Note 12, "Software and Equipment." Leases We recognize right-of-use (ROU) assets and corresponding lease liabilities for our lease arrangements. Lease liabilities are established based on the estimated present value of lease payments over the relevant lease term. We estimate a discount rate for each lease based on our estimated incremental borrowing rate at the commencement date of the relevant lease. ROU assets are measured as the associated lease liability plus any direct costs incurred in connection with the initial establishment of the lease, less any lease incentives received. Business Combinations, Goodwill and Intangible Assets Goodwill represents the excess of the purchase price over the estimated fair value of net assets acquired from a business combination. In accordance with ASC 350, Intangibles - Goodwill and Other, we test goodwill for impairment during the third quarter each year, or more frequently if we believe indicators of impairment exist. We have not identified any impairments of goodwill through December 31, 2021. Our intangible assets consist of state licenses and Fannie Mae and Freddie Mac (collectively, the GSEs) applications which have indefinite lives. We test indefinite-lived intangible assets for impairment during the fourth quarter of each year or more frequently if we believe indicators of impairment exist. We have not identified any impairments of indefinite-lived intangible assets through December 31, 2021. Premiums Receivable Premiums receivable consists of premiums due on our mortgage insurance policies. If a mortgage insurance premium is unpaid for more than 120 days, the associated receivable is written off against earned premium and the related insurance policy is canceled. We recognize an allowance for credit losses for premiums receivable based on credit losses expected to arise over the life of the receivable. Due to the nature of our insurance policies (a necessary precondition for access to mortgage credit for covered borrowers) and the short duration of the related receivables, we do not typically experience credit losses against our premium receivables and the allowance for credit loss established on premium receivables was deemed immaterial at December 31, 2021 or 2020. Premiums receivable may be written off prior to 120 days in the ordinary course of business for non-credit events including, but not limited to, the modification or refinancing of an underlying insured loan. We have established a reserve for premium write-offs based on historical experience; such reserve was $2.3 million and $1.6 million at December 31, 2021 and 2020, respectively. Variable Interest Entities NMIC is a party to reinsurance agreements with Oaktown Re Ltd., Oaktown Re II Ltd., Oaktown Re III Ltd., Oaktown Re IV Ltd., Oaktown Re V Ltd., Oaktown Re VI Ltd., and Oaktown Re VII Ltd. (special purpose reinsurance entities collectively referred to as the Oaktown Re Vehicles) effective May 2, 2017, July 25, 2018, July 30, 2019, July 30, 2020, October 29, 2020, April 27, 2021, and October 26, 2021, respectively. At inception of the respective reinsurance agreements, we determined that each of the Oaktown Re Vehicles were variable interest entities (VIEs), as defined under GAAP Accounting Standards Codification (ASC) 810, because they did not have sufficient equity at risk to finance their respective activities. We evaluated the VIEs at inception to determine whether NMIC was the primary beneficiary under each deal and, if so, whether we were required to consolidate the assets and liabilities of each VIE. The primary beneficiary of a VIE is an enterprise that (1) has the power to direct the activities of the VIE, which most significantly impact its economic performance and (2) has significant economic exposure to the VIE, i.e., the obligation to absorb losses or receive benefits that could potentially be significant. The determination of whether an entity is the primary beneficiary of a VIE is complex and requires management judgment regarding determinative factors, including the expected results of the VIE and how those results are absorbed by beneficial interest holders, as well as which party has the power to direct activities that most significantly impact the performance of the VIE. We concluded that we are not the primary beneficiary of each VIE and, as such, we do not consolidate them in our consolidated financial statements. See Note 6, "Reinsurance" for further discussion of the reinsurance arrangements. Other Revenues Other revenues represent underwriting fee revenue from our subsidiary, NMIS, which provides outsourced loan review services to mortgage loan originators. NMIS fees are earned and recognized as services are provided. Recent Accounting Pronouncements - Adopted In December 2019, the Financial Accounting Standards Board (the FASB) issued ASU 2019-12, Simplifying the Accounting for Income Taxes (Topic 740). The update eliminates certain exceptions for recognizing deferred taxes for investments, performing intra-period allocations and calculating income taxes in interim periods. The ASU also includes guidance to reduce complexity in certain income tax areas, including recognizing deferred taxes for tax goodwill and allocating taxes to members of a consolidated group. We adopted this ASU on January 1, 2021 and determined it did not have a material impact on our consolidated financial statements. Recent Accounting Pronouncements - Not Yet Adopted In August 2018, the FASB issued ASU 2018-12, Targeted Improvements to the Accounting for Long-Duration Contracts (Topic 944). The update provides guidance to the existing recognition, measurement, presentation and disclosure requirements for long-duration contracts issued by an insurance entity. The FASB subsequently issued ASU 2019-09 in November 2019 and ASU 2020-11 in November 2020, which amended the effective date for this standard and provided transition relief to facilitate early application for long duration contracts. The standard will now take effect for public business entities for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2022. We are currently evaluating the impact the adoption of this ASU will have, if any, on our consolidated financial statements. In March 2020, the FASB issued ASU 2020-04, Reference Rate Reform (Topic 848). The update provides optional guidance to ease the potential burden in accounting for reference rate reform on financial reporting. Reference rate reform refers to the global transition away from referencing the London Interbank Offered Rate (LIBOR) in financial contracts, which is expected to be discontinued during a transition period from 2021 through 2023. The ASU includes optional expedients and exceptions for applying GAAP to contracts, hedging relationships and other transactions affected by reference rate reform if certain criteria are met. This standard may be elected and applied prospectively over time from March 12, 2020 through December 31, 2022 as reference rate reform activities occur. The adoption of, and future elections under, this ASU are not expected to have a material impact on our consolidated financial statements as the ASU will ease, if warranted, the requirements for accounting for the future effects of the rate reform. We continue to monitor the impact the discontinuance of LIBOR or another reference rate will have on our contracts and other transactions. In August 2020, the FASB issued ASU 2020-06, Debt—Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging— Contracts in Entity's Own Equity (Subtopic 815-40). The update simplifies the accounting for convertible instruments and contracts on an entity's own equity, including warrants, eliminating certain triggers for derivative accounting. We adopted this ASU on January 1, 2022 and determined it did not have a material impact on our consolidated financial statements, including our warrant liability.

Investments

12 Months Ended

Dec. 31, 2021

Investments, Debt and Equity Securities [Abstract]

Investments

We hold all investments on an available-for-sale basis and evaluate each position quarterly for impairment. We recognize an impairment on a security through the statement of operations if (i) we intend to sell the impaired security; or (ii) it is more likely than not that we will be required to sell the impaired security prior to recovery of its amortized cost basis. If a sale is intended or likely to be required, we write down the amortized cost basis of the security to fair value and recognize the full amount of the impairment through the consolidated statement of operations and comprehensive income as a "Net Realized Investment Loss." To the extent we determine that a security impairment is credit-related, an impairment loss is recognized through the statement of operations as a provision for credit loss expense. The portion of a security impairment attributed to other non-credit related factors is recognized in other comprehensive income, net of taxes.

Fair Values and Gross Unrealized Gains and Losses on Investments


	Amortized Cost		Gross Unrealized				Fair Value
			Gains		Losses
As of December 31, 2021	(In Thousands)
U.S. Treasury securities and obligations of U.S. government agencies	$	29,443	$	981	$	—	$	30,424
Municipal debt securities	553,793		5,689		(5,404)		554,078
Corporate debt securities	1,388,204		22,990		(17,364)		1,393,830
Asset-backed securities	96,324		684		(427)		96,581
Total bonds	2,067,764		30,344		(23,195)		2,074,913

Short-term investments	11,009		9		—		11,018
Total investments	$	2,078,773	$	30,353	$	(23,195)	$	2,085,931


	Amortized Cost		Gross Unrealized				Fair Value
			Gains		Losses
As of December 31, 2020	(In Thousands)
U.S. Treasury securities and obligations of U.S. government agencies	$	29,412	$	2,186	$	—	$	31,598
Municipal debt securities	407,323		14,027		(2)		421,348
Corporate debt securities	1,165,260		55,014		(483)		1,219,791
Asset-backed securities	128,471		2,736		(27)		131,180
Total bonds	1,730,466		73,963		(512)		1,803,917

Short-term investments	369		—		—		369
Total investments	$	1,730,835	$	73,963	$	(512)	$	1,804,286

We did not own any mortgage-backed securities in our asset-backed securities portfolio at December 31, 2021 or 2020.

The following table presents a breakdown of the fair value of our corporate debt securities by issuer industry group as of December 31, 2021 and 2020:


	December 31, 2021		December 31, 2020
Financial	38	%	37	%
Consumer	24		23
Communications	11		10
Utilities	10		11
Technology	9		10
Industrial	8		9
Total	100	%	100	%

As of December 31, 2021 and 2020, approximately $5.6 million and $5.7 million, respectively, of our cash and investments were held in the form of U.S. Treasury securities on deposit with various state insurance departments to satisfy regulatory requirements.

Scheduled Maturities

The amortized cost and fair value of available-for-sale securities as of December 31, 2021 and 2020, by contractual maturity, are shown below. Expected maturities will differ from contractual maturities because issuers may have the right to call or prepay obligations with or without call or prepayment penalties. Because most asset-backed securities provide for periodic payments throughout their lives, they are listed below in a separate category.


As of December 31, 2021	Amortized Cost		Fair Value
	(In Thousands)
Due in one year or less	$	81,699	$	82,201
Due after one through five years	630,625		644,447
Due after five through ten years	1,215,224		1,207,997
Due after ten years	54,901		54,705
Asset-backed securities	96,324		96,581
Total investments	$	2,078,773	$	2,085,931


As of December 31, 2020	Amortized Cost		Fair Value
	(In Thousands)
Due in one year or less	$	57,429	$	57,949
Due after one through five years	507,444		536,520
Due after five through ten years	1,016,230		1,056,098
Due after ten years	21,261		22,539
Asset-backed securities	128,471		131,180
Total investments	$	1,730,835	$	1,804,286

Aging of Unrealized Losses

As of December 31, 2021, the investment portfolio had gross unrealized losses of $23.2 million, of which $6.5 million had been in an unrealized loss position for a period of twelve months or longer. As of December 31, 2020, the investment portfolio had gross unrealized losses of $512 thousand, of which $8 thousand had been in an unrealized loss position for a period of twelve months or longer. For those securities in an unrealized loss position, the length of time the securities were in such a position is as follows:


	Less Than Twelve Months					Twelve Months or Greater					Total
	# of Securities	Fair Value		Unrealized Losses		# of Securities	Fair Value		Unrealized Losses		# of Securities	Fair Value		Unrealized Losses
As of December 31, 2021		(Dollars in Thousands)

Municipal debt securities	151	$	314,823	$	(4,959)	2	$	8,138	$	(445)	153	$	322,961	$	(5,404)
Corporate debt securities	114	653,488		(11,426)		20	146,003		(5,938)		134	799,491		(17,364)
Asset-backed securities	11	57,601		(357)		1	1,977		(70)		12	59,578		(427)
Total	276	$	1,025,912	$	(16,742)	23	$	156,118	$	(6,453)	299	$	1,182,030	$	(23,195)


	Less Than Twelve Months					Twelve Months or Greater					Total
	# of Securities	Fair Value		Unrealized Losses		# of Securities	Fair Value		Unrealized Losses		# of Securities	Fair Value		Unrealized Losses
As of December 31, 2020		(Dollars in Thousands)

Municipal debt securities	4	$	3,548	$	(2)	—	$	—	$	—	4	$	3,548	$	(2)
Corporate debt securities	9	40,081		(483)		1	33		—		10	40,114		(483)
Asset-backed securities	2	5,191		(19)		1	2,495		(8)		3	7,686		(27)
Total	15	$	48,820	$	(504)	2	$	2,528	$	(8)	17	$	51,348	$	(512)

Allowance for credit losses

As of December 31, 2021 and 2020, we did not recognize an allowance for credit loss for any security in the investment portfolio and we did not record any provision for credit loss for investment securities during the years ended December 31, 2021 or 2020.

The increase in the number of securities in and the aggregate size of the unrealized loss position as of December 31, 2021, was primarily driven by interest rate movements following the purchase date of certain securities. We evaluated the securities in an unrealized loss position as of December 31, 2021 and assessed the credit ratings and any ratings changes as well as any adverse conditions specifically related to the security. Based on our estimate of the amount and timing of cash flows to be collected, we believe the unrealized losses as of December 31, 2021 are not indicative of the ultimate collectability of the current amortized cost of the securities.

Net Investment Income

The following table presents the components of net investment income:


	For the year ended December 31,
	2021		2020		2019
	(In Thousands)
Investment income	$	39,385	$	33,140	$	31,332
Investment expenses	(1,313)		(1,243)		(476)
Net investment income	$	38,072	$	31,897	$	30,856

The following table presents the components of net realized investment gains:


	For the year ended December 31,
		2021		2020		2019
		(In Thousands)
Gross realized investment gains		$	729	$	5,572	$	561
Gross realized investment losses		—		(4,642)		(516)
Net realized investment gains		$	729	$	930	$	45

Fair Value of Financial Instruments

12 Months Ended

Dec. 31, 2021

Fair Value Disclosures [Abstract]

Fair Value of Financial Instruments

The following describes the valuation techniques used by us to determine the fair value of our financial instruments:

We established a fair value hierarchy by prioritizing the inputs to valuation techniques used to measure fair value. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurements) and the lowest priority to unobservable inputs (Level 3 measurements). The three levels of the fair value hierarchy under this standard are described below:

Level 1 - Fair value measurements based on quoted prices in active markets that we have the ability to access for identical assets or liabilities. Market price data generally is obtained from exchange or dealer markets. We do not adjust the quoted price for such instruments.

Level 2 - Fair value measurements based on inputs other than quoted prices included in Level 1 that are observable for the asset or liability, either directly or indirectly. Level 2 inputs include quoted prices for similar assets and liabilities in active markets, quoted prices for identical or similar assets or liabilities in markets that are not active, and inputs other than quoted prices that are observable for the asset or liability, such as interest rates and yield curves that are observable at commonly quoted intervals.

Level 3 - Fair value measurements based on valuation techniques that use significant inputs that are unobservable. Both observable and unobservable inputs may be used to determine the fair values of positions classified in Level 3. The circumstances for using these measurements include those in which there is little, if any, market activity for the asset or liability. Therefore, we must make certain assumptions, which require significant management judgment or estimation about the inputs a hypothetical market participant would use to value that asset or liability.

In certain cases, the inputs used to measure fair value may fall into different levels of the fair value hierarchy. In such cases, the level in the fair value hierarchy is determined based on the lowest level input that is significant to the fair value measurement in its entirety.

Assets classified as Level 1 and Level 2

To determine the fair value of securities available-for-sale in Level 1 and Level 2 of the fair value hierarchy, independent pricing sources have been utilized. One price is provided per security based on observable market data. To ensure securities are appropriately classified in the fair value hierarchy, we review the pricing techniques and methodologies of the independent pricing sources and believe that their policies adequately consider market activity, either based on specific transactions for the issue valued or based on modeling of securities with similar credit quality, duration, yield and structure that were recently traded. A variety of inputs are utilized by the independent pricing sources including benchmark yields, reported trades, non-binding broker/dealer quotes, issuer spreads, two sided markets, benchmark securities, bids, offers and reference data including data published in market research publications. Inputs may be weighted differently for any security, and not all inputs are used for each security evaluation. Market indicators, industry and economic events are also considered. This information is evaluated using a multidimensional pricing model. Quality controls are performed by the independent pricing sources throughout this process, which include reviewing tolerance reports, trading information and data changes, and directional moves compared to market moves. This model combines all inputs to arrive at a value assigned to each security. We have not made any adjustments to the prices obtained from the independent pricing sources.

Liabilities classified as Level 3

We calculate the fair value of outstanding warrants utilizing Level 3 inputs, including a Black-Scholes option-pricing model, in combination with a binomial model, and we value the pricing protection features within the warrants using a Monte-Carlo simulation model. Variables in the model include the risk-free rate of return, dividend yield, expected life and expected volatility of our stock price.

The following tables present the level within the fair value hierarchy at which our financial instruments were measured:


	Fair Value Measurements Using
	Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Fair Value
As of December 31, 2021	(In Thousands)
U.S. Treasury securities and obligations of U.S. government agencies	$	30,424	$	—	$	—	$	30,424
Municipal debt securities	—		554,078		—		554,078
Corporate debt securities	—		1,393,830		—		1,393,830
Asset-backed securities	—		96,581		—		96,581

Cash, cash equivalents and short-term investments	87,664		—		—		87,664
Total assets	$	118,088	$	2,044,489	$	—	$	2,162,577
Warrant liability	—		—		2,363		2,363
Total liabilities	$	—	$	—	$	2,363	$	2,363


	Fair Value Measurements Using
	Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Fair Value
As of December 31, 2020	(In Thousands)
U.S. Treasury securities and obligations of U.S. government agencies	$	31,598	$	—	$	—	$	31,598
Municipal debt securities	—		421,348		—		421,348
Corporate debt securities	—		1,219,791		—		1,219,791
Asset-backed securities	—		131,180		—		131,180

Cash, cash equivalents and short-term investments	127,306		—		—		127,306
Total assets	$	158,904	$	1,772,319	$	—	$	1,931,223
Warrant liability	—		—		4,409		4,409
Total liabilities	$	—	$	—	$	4,409	$	4,409

There were no transfers between Level 2 and Level 3 of the fair value hierarchy during the years ended December 31, 2021 or 2020.

The following table provides a roll-forward of Level 3 liabilities measured at fair value:


	For the year ended December 31,
Warrant Liability	2021		2020		2019
	(In Thousands)
Balance, January 1	$	4,409	$	7,641	$	7,296
Change in fair value of warrant liability included in earnings	(566)		(2,907)		8,657
Issuance of common stock on warrant exercise	(1,480)		(325)		(8,312)
Balance, December 31	$	2,363	$	4,409	$	7,641

The following table outlines the key inputs and assumptions used to calculate the fair value of the warrant liability in the Black-Scholes option-pricing model as of the dates indicated:


	As of December 31,
	2021			2020			2019
Common stock price	$	21.85		$	22.65		$	33.18
Risk free interest rate	0.07		%	0.11		%	1.59		%
Expected life	0.31 years			1.31 years			2.31 years
Expected volatility	26.3		%	83.7		%	41.4		%
Dividend yield	—		%	—		%	—		%

The changes in fair value of the warrant liability for the years ended December 31, 2021, 2020, and 2019 were driven by the exercise of outstanding warrants, as well as changes in the price of our common stock and other Black-Scholes model inputs during the respective periods.

Financial Instruments not Measured at Fair Value

On June 19, 2020, we issued $400 million aggregate principal amount of senior secured notes that mature on June 1, 2025 (the Notes) and used a portion of the proceeds from the Notes offering to repay the outstanding amount due under our $150 million term loan (2018 Term Loan). At December 31, 2021, the Notes were carried at a cost of $394.6 million, net of unamortized debt issuance costs of $5.4 million, and had a fair value of $454.6 million as assessed under our Level 2 hierarchy. At December 31, 2020, the Notes were carried at a cost of $393.3 million, net of unamortized debt issuance costs of $6.7 million, and had a fair value of $447.1 million.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Debt	12 Months Ended
Debt	Dec. 31, 2021
Debt Disclosure [Abstract]
Debt	Debt Senior Secured Notes At December 31, 2021, we had $400 million aggregate principal amount of senior secured notes outstanding. The Notes were issued pursuant to an indenture dated June 19, 2020 (the Indenture) and bear interest at a rate of 7.375%, payable semi-annually on June 1 and December 1. $244.4 million of proceeds from the Notes offering were contributed to our lead operating subsidiary, NMIC and remaining proceeds were used to repay the outstanding amount due under the 2018 Term Loan due on May 24, 2023 and to pay underwriting fees incurred connection with the offering. The Notes mature on June 1, 2025. At any time, or from time to time, prior to March 1, 2025, we may elect to redeem the Notes in whole or in part at a price based on 100% of the aggregate principal amount of any Notes redeemed plus the "Applicable Premium," plus accrued and unpaid interest thereon. Applicable Premium is defined as the greater of (1) 1.0% of the principal amount of the Notes, or (2) the excess of the present value of the principal value of the Notes plus all future interest payments over the principal amount. At any time on or after March 1, 2025, we may elect to redeem the Notes in whole or in part at a price equal to 100% of the aggregate principal amount of the Notes to be redeemed plus accrued and unpaid interest thereon. From time to time prior to June 1, 2022, we may also elect to use proceeds raised from one or more equity offerings to redeem up to 40% of the aggregate principal amount of the Notes at a price equal to 107.375% of the aggregate principal amount thereof plus accrued and unpaid interest thereon, subject to certain exceptions. Interest expense for the Notes includes interest and the amortization of capitalized debt issuance costs. In connection with the Notes offering, we recorded capitalized debt issuance costs of $7.4 million. Such amounts will be amortized over the contractual life of the Notes using the effective interest method. At December 31, 2021 and 2020, approximately $5.4 million and $6.7 million, respectively, of unamortized debt issuance costs remained. Interest expense for the year ended December 31, 2020 includes $2.6 million of costs related to the extinguishment of the 2018 Term Loan and issuance of the Notes. At December 31, 2021 and 2020, $2.5 million of accrued and unpaid interest on the Notes is included in "Accounts Payable and Accrued Expenses" on the consolidated balance sheet. 2021 Revolving Credit Facility On November 29, 2021, we amended our $110 million senior secured revolving credit facility (the 2020 Revolving Credit Facility and as amended, the 2021 Revolving Credit Facility), expanding the lender group, increasing the revolving capacity to $250 million, and extending the maturity from February 22, 2023 to the earlier of (x) November 29, 2025, or (y) if any existing senior secured notes remain outstanding on such date, February 28, 2025. Borrowings under the 2021 Revolving Credit Facility may be used for general corporate purposes, including to support the growth of our new business production and operations, and accrue interest at a variable rate equal to, at our discretion, (i) a Base Rate (as defined in the 2021 Revolving Credit Facility) subject to a floor of 1.00% per annum) plus a margin of 0.375% to 1.875% per annum or (ii) the Adjusted Term SOFR Rate (as defined in the 2021 Revolving Credit Facility) plus a margin of 1.375% to 2.875% per annum, with the margin in each of (i) or (ii) based on our applicable corporate credit rating at the time. As of December 31, 2021 and 2020, no amounts were drawn under the 2021 or 2020 Revolving Credit Facilities, respectively. Under the 2021 Revolving Credit Facility, we are required to pay a quarterly commitment fee on the average daily undrawn amount of 0.175% to 0.525%, based on the applicable corporate credit rating at the time. As of December 31, 2021, the applicable commitment fee was 0.35%. For the year ended December 31, 2021, we recorded $0.4 million of commitment fees in interest expense. We incurred debt issuance costs of $1.1 million in connection with the 2021 Revolving Credit Facility, and had $0.6 million of unamortized debt issuance costs associated with the 2020 Revolving Credit Facility remaining at the time of its amendment and replacement. Combined unamortized debt issuance will be amortized through interest expense on a straight-line basis over the contractual life of the 2021 Revolving Credit Facility. At December 31, 2021, remaining unamortized deferred debt issuance costs were $1.6 million. We are subject to certain covenants under the 2021 Revolving Credit Facility, including, but not limited to, the following: a maximum debt-to-total capitalization ratio of 35%, compliance with the private mortgage insurer eligibility requirements (PMIERs) financial requirements (subject to any GSE approved waivers), and minimum consolidated net worth and statutory capital requirements (respectively, as defined therein). We were in compliance with all covenants at December 31, 2021.

- Definition

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-URI http://asc.fasb.org/topic&trid=2208564

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1B
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1C
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495334-112611

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1I
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495371-112611

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1I
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495371-112611

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(c))
-URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1C
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495334-112611

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1C
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495334-112611

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1E
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495348-112611

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1I
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495371-112611

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1B
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611

+ Details

Reinsurance

12 Months Ended

Dec. 31, 2021

Reinsurance Disclosures [Abstract]

Reinsurance

We enter into third-party reinsurance transactions to actively manage our risk, ensure compliance with PMIERs, state regulatory and other applicable capital requirements, (respectively, as defined therein), and support the growth of our business. The Wisconsin Office of the Commissioner of Insurance (Wisconsin OCI) has approved and the GSEs have indicated their non-objection to all such transactions (subject to certain conditions and ongoing review, including levels of approved capital credit).

The effect of our reinsurance agreements on premiums written and earned is as follows:


	For the year ended
	December 31, 2021		December 31, 2020		December 31, 2019
	(In Thousands)
Net premiums written
Direct	$	557,050	$	455,172	$	376,052
Ceded (1)	(88,539)		(66,528)		(43,400)
Net premiums written	$	468,511	$	388,644	$	332,652

Net premiums earned
Direct	$	536,630	$	472,998	$	398,303
Ceded (1)	(92,336)		(75,826)		(53,288)
Net premiums earned	$	444,294	$	397,172	$	345,015

(1) Net of profit commission.

Excess-of-loss reinsurance

NMIC is party to reinsurance agreements with the Oaktown Re Vehicles that provide it with aggregate excess-of-loss reinsurance coverage on defined portfolios of mortgage insurance policies. Under each agreement, NMIC retains a first layer of

aggregate loss exposure on covered policies and the respective Oaktown Re Vehicle then provides second layer loss protection up to a defined reinsurance coverage amount. NMIC then retains losses in excess of the respective reinsurance coverage amounts.

NMIC makes risk premium payments to the Oaktown Re Vehicles for the applicable outstanding reinsurance coverage amount and pays an additional amount for anticipated operating expenses (capped at $250 thousand per year, except with respect to Oaktown Re Ltd., for which the cap is $300 thousand per year). NMIC ceded aggregate premiums to the Oaktown Re Vehicles of $41.3 million, $22.8 million and $14.6 million during the years ended December 31, 2021, 2020 and 2019, respectively. The increase in premiums ceded year-on-year is due to the inception of the excess-of-loss reinsurance agreements that NMIC entered in with Oaktown Re IV Ltd. and Oaktown Re V Ltd. in 2020 and Oaktown Re VI Ltd. and Oaktown VII Ltd. in 2021.

NMIC applies claims paid on covered policies against its first layer aggregate retained loss exposure under each excess-of-loss agreement. NMIC did not cede any incurred losses on covered policies to the Oaktown Re Vehicles during the years ended December 31, 2021, 2020 and 2019, as the aggregate first layer risk retention for each applicable agreement was not exhausted during such periods.

Under the terms of each excess-of-loss reinsurance agreement, the Oaktown Re Vehicles are required to fully collateralize their outstanding reinsurance coverage amount to NMIC with funds deposited into segregated reinsurance trusts. Such trust funds are required to be invested in short-term U.S. Treasury money market funds at all times. Each Oaktown Re Vehicle financed its respective collateral requirement through the issuance of mortgage insurance-linked notes to unaffiliated investors. Such insurance-linked notes mature ten years from the inception date of each reinsurance agreement (except the notes issued by Oaktown Re VI Ltd. and Oaktown Re VII Ltd., which have a 12.5 year maturity). We refer to NMIC's reinsurance agreements with and the insurance-linked note issuances by Oaktown Re Vehicles individually as the 2017 ILN Transaction, 2018 ILN Transaction, 2019 ILN Transaction, 2020-1 ILN Transaction, 2020-2 ILN Transaction, 2021-1 ILN Transaction, and 2021-2 ILN Transaction, and collectively as the ILN Transactions.

The respective reinsurance coverage amounts provided by the Oaktown Re Vehicles decrease over a ten-year period as the underlying insured mortgages are amortized or repaid, and/or the mortgage insurance coverage is canceled (except the coverage provided by Oaktown Re VI Ltd. and Oaktown Re VII Ltd., which decreases over a 12.5 year period). As the reinsurance coverage decreases, a prescribed amount of collateral held in trust by the Oaktown Re Vehicles is distributed to ILN Transaction noteholders as amortization of the outstanding insurance-linked note principal balances. The outstanding reinsurance coverage amounts stop amortizing, and the collateral distribution to ILN Transaction noteholders and amortization of insurance-linked note principal is suspended if certain credit enhancement or delinquency thresholds, as defined in each agreement, are triggered (each, a Lock-Out Event). A Lock-Out Event was deemed to have occurred, effective June 25, 2020 for each of the 2017, 2018 and 2019 ILN Transactions (related to the default experience of the underlying reference pools for each respective transaction) and at inception of the 2021-1 and 2021-2 ILN Transactions (related to the initial build of their target credit enhancement levels), and the amortization of reinsurance coverage, and distribution of collateral assets and amortization of insurance-linked notes was suspended for each such ILN Transaction. The amortization of reinsurance coverage, distribution of collateral assets and amortization of insurance-linked notes will remain suspended for the duration of the Lock-Out Event for each such ILN Transaction, and during such period assets will be preserved in the applicable reinsurance trust account to collateralize the excess-of-loss reinsurance coverage provided to NMIC. Effective November 30, 2021, the Lock-Out Event for the 2017 ILN Transaction was deemed to have cleared and amortization of the associated reinsurance coverage, and distribution of collateral assets and amortization of the associated insurance-linked notes resumed.

The following table presents the inception date, covered production period, initial and current reinsurance coverage amount, and initial and current first layer retained aggregate loss under each of the ILN Transactions. Current amounts are presented as of December 31, 2021.


($ values in thousands)	Inception Date	Covered Production	Initial Reinsurance Coverage	Current Reinsurance Coverage	Initial First Layer Retained Loss	Current First Layer Retained Loss (1)
2017 ILN Transaction	May 2, 2017	1/1/2013 - 12/31/2016	$211,320	$27,425	$126,793	$121,163
2018 ILN Transaction	July 25, 2018	1/1/2017 - 5/31/2018	264,545	158,489	125,312	122,569
2019 ILN Transaction	July 30, 2019	6/1/2018 - 6/30/2019	326,905	231,877	123,424	122,548
2020-1 ILN Transaction	July 30, 2020	7/1/2019 - 3/31/2020	322,076	49,879	169,514	169,488
2020-2 ILN Transaction	October 29, 2020	4/1/2020 - 9/30/2020 (2)	242,351	155,129	121,777	121,177
2021-1 ILN Transaction (5)	April 27, 2021	10/1/2020 - 3/31/2021 (3)	367,238	367,238	163,708	163,708
2021-2 ILN Transaction (5)	October 26, 2021	4/1/2021 - 9/30/2021 (4)	363,596	363,596	146,229	146,229

(1) NMIC applies claims paid on covered policies against its first layer aggregate retained loss exposure and cedes reserves for incurred claims and claims expenses to each applicable ILN Transaction and recognizes a reinsurance recoverable if such incurred claims and claims expenses exceed its current first layer retained loss.

(2) Approximately 1% of the production covered by the 2020-2 ILN Transaction has coverage reporting dates between July 1, 2019 and March 31, 2020.

(3) Approximately 1% of the production covered by the 2021-1 ILN Transaction has coverage reporting dates between July 1, 2019 and September 30, 2020.

(4) Approximately 2% of the production covered by the 2021-2 ILN Transaction has coverage reporting dates between July 1, 2019 and March 31, 2021.

(5) As of December 31, 2021, the current reinsurance coverage amount on the 2021-1 ILN and 2021-2 ILN Transactions is equal to the initial reinsurance coverage amount, as the reinsurance coverage provided by the associated Oaktown Re vehicles will not decrease until a target credit enhancement level is met.

NMIC holds optional termination rights under each ILN Transaction, including, among others, an optional call feature which provides NMIC the discretion to terminate the transaction on or after a prescribed date, and a clean-up call if the outstanding reinsurance coverage amount amortizes to 10% or less of the reinsurance coverage amount at inception or if NMIC reasonably determines that changes to GSE or rating agency asset requirements would cause a material and adverse effect on the capital treatment afforded to NMIC under a given agreement. In addition, there are certain events that trigger mandatory termination of an agreement, including NMIC's failure to pay premiums or consent to reductions in a trust account to make principal payments to noteholders, among others.

Under the terms of the 2018, 2019, and 2020-1 ILN Transactions, we are required to maintain a certain level of restricted funds in premium deposit accounts with Bank of New York Mellon until the respective notes have been redeemed in full. "Cash and cash equivalents" on our consolidated balance sheet includes restricted amounts of $3.2 million and $5.6 million as of December 31, 2021 and 2020, respectively. We are not required to deposit additional funds into the premium deposit accounts in the future and the restricted balances required under these transactions will decline over time as the outstanding principal balance of the respective insurance-linked notes are amortized.

Quota share reinsurance

NMIC is a party to five active quota share reinsurance treaties – the 2016 QSR Transaction, effective September 1, 2016, the 2018 QSR Transaction, effective January 1, 2018 and the 2020 QSR Transaction, effective April 1, 2020, the 2021 QSR Transaction, effective January 1, 2021 and the 2022 QSR Transaction, effective October 1, 2021 – which we refer to collectively as the QSR Transactions. Under each of the QSR Transactions, NMIC cedes a proportional share of its risk on eligible policies written during a discrete period to panels of third-party reinsurance providers. Each of the third-party reinsurance providers has an insurer financial strength rating of A- or better by Standard & Poor's Rating Service (S&P), A.M. Best Company, Inc. (A.M. Best) or both.

Under the terms of the 2016 QSR Transaction, NMIC cedes premiums written related to 25% of the risk on eligible primary policies written for all periods through December 31, 2017 and 100% of the risk under our pool agreement with Fannie Mae. The 2016 QSR Transaction is scheduled to terminate on December 31, 2027, except with respect to the ceded pool risk, which is scheduled to terminate on August 31, 2023. NMIC has the option, based on certain conditions and subject to a termination fee, to terminate the agreement as of December 31, 2020, or at the end of any calendar quarter thereafter, which would result in NMIC recapturing the related risk.

Under the terms of the 2018 QSR Transaction, NMIC cedes premiums earned related to 25% of the risk on eligible policies written in 2018 and 20% of the risk on eligible policies written in 2019. The 2018 QSR Transaction is scheduled to terminate on December 31, 2029. NMIC has the option, based on certain conditions and subject to a termination fee, to terminate the agreement as of December 31, 2022, or at the end of any calendar quarter thereafter, which would result in NMIC recapturing the related risk.

Under the terms of the 2020 QSR Transaction, NMIC cedes premiums earned related to 21% of the risk on eligible policies written from April 1, 2020 to December 31, 2020. The 2020 QSR Transaction is scheduled to terminate on December 31, 2030. NMIC has the option, based on certain conditions and subject to a termination fee, to terminate the agreement as of December 31, 2023, or at the end of any calendar quarter thereafter, which would result in NMIC recapturing the related risk.

Under the terms of the 2021 QSR Transaction, NMIC cedes premiums earned related to 22.5% of the risk on eligible policies written in 2021, subject to an aggregate risk written limit which was exhausted on October 30, 2021. The 2021 QSR Transaction is scheduled to terminate on December 31, 2031. NMIC has the option, based on certain conditions and subject to a termination fee, to terminate the agreement as of December 31, 2024, or at the end of any calendar quarter thereafter, which would result in NMIC recapturing the related risk.

Under the terms of the 2022 QSR Transaction, NMIC cedes premiums earned related to 20% of the risk on eligible policies written primarily between October 30, 2021 and December 31, 2022. The 2022 QSR Transaction is scheduled to

terminate on December 31, 2032. NMIC has the option, based on certain conditions and subject to a termination fee, to terminate the agreement as of December 31, 2024 or semi-annually thereafter, which would result in NMIC recapturing the related risk.

In connection with the 2022 QSR Transaction, NMIC entered into an additional back-to-back quota share agreement that is scheduled to incept on January 1, 2023 (the 2023 QSR Transaction). Under the terms of the 2023 QSR Transactions, NMIC will cede premiums earned related to 20% of the risk on eligible policies written in 2023. The 2023 QSR Transaction is scheduled to terminate on December 31, 2033. NMIC has the option, based on certain conditions and subject to a termination fee, to terminate the agreement as of December 31, 2025 or semi-annually thereafter, which would result in NMIC recapturing the related risk.

NMIC may terminate any or all of the QSR Transactions without penalty if, due to a change in PMIERs requirements, it is no longer able to take full PMIERs asset credit for the RIF ceded under the respective agreements. Additionally, under the terms of the QSR Transactions, NMIC may elect to selectively terminate its engagement with individual reinsurers on a run-off basis (i.e., reinsurers continue providing coverage on all risk ceded prior to the termination date, with no new cessions going forward) or cut-off basis (i.e., the reinsurance arrangement is completely terminated with NMIC recapturing all previously ceded risk) under certain circumstances. Such selective termination rights arise when, among other reasons, a reinsurer experiences a deterioration in its capital position below a prescribed threshold and/or a reinsurer breaches (and fails to cure) its collateral posting obligations under the relevant agreement.

Effective April 1, 2019, NMIC elected to terminate its engagement with one reinsurer under the 2016 QSR Transaction on a cut-off basis. In connection with the termination, NMIC recaptured approximately $500 million of previously ceded primary RIF and stopped ceding new premiums earned or written with respect to the recaptured risk. With the termination, ceded premiums written under the 2016 QSR Transaction decreased from 25% to 20.5% on eligible policies. The termination has no effect on the cession of pool risk under the 2016 QSR Transaction.

The following table shows amounts related to the QSR Transactions:


	For the year ended
	December 31, 2021		December 31, 2020		December 31, 2019
	(In Thousands)
Ceded risk-in-force	$	8,194,604	$	5,543,969	$	5,137,249

Ceded premiums earned	(110,140)		(94,899)		(89,211)
Ceded claims and claim expenses	3,233		14,002		3,465

Ceding commission earned	23,473		18,526		17,652
Profit commission	59,104		41,902		50,513

Ceded premiums written under the 2016 QSR Transaction are recorded on the balance sheet as prepaid reinsurance premiums and amortized to ceded premiums earned in a manner consistent with the recognition of revenue on direct premiums. Under all other QSR Transactions, premiums are ceded on an earned basis as defined in the agreement. NMIC receives a 20% ceding commission for premiums ceded under the QSR Transactions. NMIC also receives a profit commission under each of the QSR Transactions, provided that the loss ratios on loans covered under the 2016, 2018, 2020, 2021 and 2022 QSR Transactions, generally remain below 60%, 61%, 50%, 57.5% and 62%, respectively, as measured annually. Ceded claims and claim expenses under each of the QSR Transactions reduce the respective profit commission received by NMIC on a dollar-for-dollar basis.

In accordance with the terms of the 2016 QSR Transaction, rather than making a cash payment or transferring investments for ceded premiums written, NMIC established a funds withheld liability, which also includes amounts due to NMIC for ceding and profit commissions. Any loss recoveries and any potential profit commission to NMIC will be realized from this account until exhausted. NMIC's reinsurance recoverable balance is further supported by trust accounts established and maintained by each reinsurer in accordance with the PMIERs funding requirements for risk ceded to non-affiliates. The reinsurance recoverable on loss reserves related to the 2016 QSR Transaction was $4.6 million as of December 31, 2021.

In accordance with the terms of the 2016, 2018, 2020, 2021 and 2022 QSR Transactions, cash payments for ceded premiums earned are settled on a quarterly basis, offset by amounts due to NMIC for ceding and profit commissions. Any loss recoveries and any potential profit commission to NMIC are also recognized quarterly. NMIC's reinsurance recoverable balance is supported by trust accounts established and maintained by each reinsurer in accordance with the PMIERs funding requirements for risk ceded to non-affiliates. The aggregate reinsurance recoverable on loss reserves related to the 2018, 2020, 2021 and 2022 QSR Transactions was $15.7 million as of December 31, 2021.

Reserve for Insurance Claims and Claim Expenses

12 Months Ended

Dec. 31, 2021

Insurance [Abstract]

Reserves for Insurance Claims and Claim Expenses

We hold gross reserves in an amount equal to the estimated liability for insurance claims and claim expenses related to defaults on insured mortgage loans. A loan is considered to be in "default" as of the payment date at which a borrower has missed the preceding two or more consecutive monthly payments. We establish reserves for loans that have been reported to us in default by servicers, referred to as case reserves, and additional loans that we estimate (based on actuarial review and other factors) to be in default that have not yet been reported to us by servicers, referred to as incurred but not reported (IBNR) reserves. We also establish reserves for claim expenses, which represent the estimated cost of the claim administration process, including legal and other fees, as well as other general expenses of administering the claim settlement process. As of December 31, 2021, we had 6,227 primary loans in default and held gross reserves for insurance claims and claim expenses of $103.6 million. During the year ended December 31, 2021, we paid 82 claims totaling $2.6 million, including 79 claims covered under the QSR Transactions representing $0.5 million of ceded claims and claim expenses.

In 2013, we entered into a pool insurance transaction with Fannie Mae. The pool transaction includes a deductible, which represents the amount of claims to be absorbed by Fannie Mae before we are obligated to pay any claims. We only establish reserves for pool risk if we expect claims to exceed this deductible. At December 31, 2021, 96 loans in the pool were in default. These 96 loans represented approximately $7.3 million of RIF. Due to the size of the remaining deductible, our expectation that a limited number of loans in default will progress to a claim and the expected severity on such claim submissions (all loans in the pool had loan-to-value (LTV) ratios under 80% at origination), we did not establish any case or IBNR reserves for pool risk at December 31, 2021. In connection with the settlement of pool claims, we applied $1.0 million to the pool deductible through December 31, 2021. At December 31, 2021, the remaining pool deductible was $9.4 million. We have not paid any pool claims to date. 100% of our pool RIF is reinsured under the 2016 QSR Transaction.

We had 6,227 loans in default in our primary insured portfolio as of December 31, 2021 which represented a 1.22% default rate against 512,316 total policies in-force. We had 12,209 loans in default in our primary insured portfolio as of December 31, 2020, which represented a 3.06% default rate against 399,429 total policies in-force. Although our default count declined from December 31, 2020 to December 31, 2021, the population remains elevated compared to our historical experience due to the continued challenges certain borrowers are facing related to the COVID-19 pandemic and their decision to access the forbearance program for federally backed loans codified under the Coronavirus Aid, Relief and Economic Security Act (CARES Act) or similar programs made available by private lenders.

The size of the reserve we establish for each defaulted loan (and by extension our aggregate reserve for claims and claim expenses) reflects our best estimate of the future claim payment to be made for each individual loan in default. Our future claims exposure is a function of the number of defaulted loans that progress to claim payment (which we refer to as frequency) and the amount to be paid to settle such claims (which we refer to as severity). Our estimates of claims frequency and severity are not formulaic, rather they are broadly synthesized based on historical observed experience for similarly situated loans and assumptions about future macroeconomic factors. We generally observe that forbearance programs are an effective tool to bridge dislocated borrowers from a time of acute stress to a future date when they can resume timely payment of their mortgage obligations. The effectiveness of forbearance programs is enhanced by the availability of various repayment and loan modification options which allow borrowers to amortize or, in certain instances, outright defer payments otherwise due during the forbearance period over an extended length of time. In response to the COVID-19 pandemic, the FHFA and GSEs introduced new repayment and loan modification options to further assist borrowers with their transition out of forbearance programs and default status.

Our reserve setting process considers the beneficial impact of forbearance, foreclosure moratorium and other assistance programs available to defaulted borrowers. At December 31, 2021 and 2020, we generally established lower reserves for defaults that we consider to be connected to the COVID-19 pandemic given our expectation that forbearance, repayment and modification, and other assistance programs will aid affected borrowers and drive higher cure rates on such defaults than we would otherwise expect to experience on similarly situated loans that did not benefit from broad-based assistance programs.

The following table provides a reconciliation of the beginning and ending gross reserve balances for primary insurance claims and claim expenses:


	For the year ended
	December 31, 2021		December 31, 2020		December 31, 2019
	(In Thousands)
Beginning balance	$	90,567	$	23,752	$	12,811
Less reinsurance recoverables (1)	(17,608)		(4,939)		(3,001)
Beginning balance, net of reinsurance recoverables	72,959		18,813		9,810

Add claims incurred:
Claims and claim expenses incurred:
Current year (2)	23,433		66,943		14,737
Prior years (3)	(11,128)		(7,696)		(2,230)
Total claims and claim expenses incurred	12,305		59,247		12,507

Less claims paid:
Claims and claim expenses paid:
Current year (2)	16		586		204
Prior years (3)	2,017		4,515		3,849
Reinsurance terminations (4)	—		—		(549)
Total claims and claim expenses paid	2,033		5,101		3,504

Reserve at end of period, net of reinsurance recoverables	83,231		72,959		18,813
Add reinsurance recoverables (1)	20,320		17,608		4,939
Ending balance	$	103,551	$	90,567	$	23,752

(1) Related to ceded losses recoverable under the QSR Transactions. See Note 6, "Reinsurance" for additional information.

(2) Related to insured loans with their most recent defaults occurring in the current year. For example, if a loan defaulted in a prior year and subsequently cured and later re-defaulted in the current year, the default would be included in the current year. Amounts are presented net of reinsurance and included $18.1 million attributed to net case reserves and $4.7 million attributed to net IBNR reserves for the year ended December 31, 2021, $60.8 million attributed to net case reserves and $5.0 million attributed to net IBNR reserves for year ended December 31, 2020, and $13.2 million attributed to net case reserves and $1.3 million attributed to net IBNR reserves for year ended December 31, 2019.

(3) Related to insured loans with defaults occurring in prior years, which have been continuously in default before the start of the current year. Amounts are presented net of reinsurance and included $6.3 million attributed to net case reserves and $5.0 million attributed to net IBNR reserves for the year ended December 31, 2021, $6.2 million attributed to net case reserves and $1.3 million attributed to net IBNR reserves for the year ended December 31, 2020, and $1.5 million attributed to net case reserves and $0.7 million attributed to net IBNR reserves for year ended December 31, 2019.

(4) Represents the settlement of reinsurance recoverables in conjunction with the termination of one reinsurer under the 2016 QSR Transaction on a cut-off basis. See Note 6, "Reinsurance" for additional information.

The "claims incurred" section of the table above shows claims and claim expenses incurred on defaults occurring in current and prior years, including IBNR reserves and is presented net of reinsurance. We may increase or decrease our claim estimates and reserves as we learn additional information about individual defaulted loans, and continue to observe and analyze loss development trends in our portfolio. Gross reserves of $74.4 million related to prior year defaults remained as of December 31, 2021.

The following tables provide claim development data by accident year and a reconciliation to the reserve for insurance claims and claim expenses:


	Cumulative Incurred Claims and Allocated Claims Adjustment Expenses, net of Reinsurance (1)																		As of December 31, 2021
Accident Year	2013		2014		2015		2016		2017		2018		2019		2020		2021		Total of IBNR		Defaults (2)
($ Values In Thousands)
2013	$	—	$	—	$	—	$	—	$	—	$	—	$	—	$	—	$	—	$	—	—
2014			83		34		4		4		4		4		4		4		—		—
2015					699		664		743		764		894		894		894		—		—
2016							2,394		1,568		1,790		1,934		1,936		1,930		4		3
2017									6,028		3,475		3,570		3,807		3,716		5		9
2018											7,779		5,271		4,709		4,533		56		47
2019													14,391		7,229		5,781		192		228
2020															65,769		56,154		4,112		2,547
2021																	22,847		362		3,393
															Total		$	95,859	$	4,731	6,227

(1) Amounts include case and IBNR reserves.

(2) Number of defaults outstanding as of December 31, 2021.


	Cumulative Paid Claims and Claims Adjustment Expenses, net of Reinsurance
Accident Year	2013		2014		2015		2016		2017		2018		2019		2020		2021
	(In Thousands)
2013	$	—	$	—	$	—	$	—	$	—	$	—	$	—	$	—	$	—
2014			—		4		4		4		4		4		4		4
2015					50		246		684		720		804		894		894
2016							171		890		1,596		1,826		1,827		1,877
2017									27		1,655		2,925		3,494		3,640
2018											130		1,981		3,537		3,780
2019													69		2,368		3,212
2020															586		1,320
2021																	16
															Total		$	14,743


Reconciliation of Disclosure of Incurred and Paid Claims Development to the Liability for Unpaid Claims and Claim Adjustment Expenses
(In Thousands)
	As of December 31, 2021
Cumulative Incurred Claims and Allocated Claims Adjustment Expenses, net of Reinsurance	$	95,859
Cumulative Paid Claims and Claims Adjustment Expenses, net of Reinsurance	14,743
Liabilities for unpaid claims and allocated claims adjustment expenses, net of reinsurance	81,116
Reinsurance recoverable on unpaid claims	20,320
Unallocated claims adjustment expenses	2,115
Total gross liability for unpaid claims and claim adjustment expenses	$	103,551

The following table shows the average percentage of claims and allocated claims adjustment expenses paid in the years following the incurrence of a claim:


	Average annual percentage payout of incurred claims and allocated claims adjustment expenses by age, net of reinsurance
	Year 1	Year 2	Year 3	Year 4	Year 5	Year 6	Year 7	Year 8
Claims duration disclosure	2%	32%	82%	93%	96%	99%	100%	100	%

Earnings per Share

12 Months Ended

Dec. 31, 2021

Earnings Per Share [Abstract]

Earnings per Share

Basic EPS is based on the weighted average number of shares of common stock outstanding. Diluted EPS is based on the weighted average number of shares of common stock outstanding and common stock equivalents that would be issuable upon the vesting of service based and performance and service-based restricted stock units (RSUs), and the exercise of vested and unvested stock options and outstanding warrants. The number of shares issuable for RSUs subject to performance and service based vesting requirements are only included in diluted shares if the relevant performance measurement period has commenced and results during such period meet the necessary performance criteria.

The following table reconciles the net income and the weighted average shares of common stock outstanding used in the computations of basic and diluted EPS of common stock:


	For the year ended December 31,
		2021		2020		2019
		(In Thousands, except for per share data)
Net income		$	231,130	$	171,566	$	171,957
Basic weighted average shares outstanding		85,620		78,023		67,573
Basic earnings per share		$	2.70	$	2.20	$	2.54

Net income		$	231,130	$	171,566	$	171,957
Gain from change in fair value of warrant liability		(566)		(2,907)		—
Diluted net income		$	230,564	$	168,659	$	171,957

Basic weighted average shares outstanding		85,620		78,023		67,573
Dilutive effect of issuable shares		1,265		1,240		2,148
Diluted weighted average shares outstanding		86,885		79,263		69,721

Diluted earnings per share		$	2.65	$	2.13	$	2.47

Anti-dilutive shares		3		58		565

Warrants	12 Months Ended
Warrants	Dec. 31, 2021
Debt Disclosure [Abstract]
Warrants	Warrants We issued 992 thousand warrants in connection with a private placement of our common stock in April 2012, of which 199 thousand remained outstanding available for exercise at December 31, 2021. Each warrant gives the holder thereof the right to purchase one share of common stock at an exercise price equal to $10.00. The warrants were issued with an aggregate fair value of $5.1 million. During the year ended December 31, 2021, 113 thousand warrants were exercised resulting in the issuance of 86 thousand shares of common stock. Upon exercise, we reclassified approximately $1.5 million of warrant fair value from warrant liability to additional paid-in capital. During the year ended December 31, 2020, 18 thousand warrants were exercised resulting in the issuance of 11 thousand shares of common stock. Upon exercise, we reclassified approximately $0.3 million of warrant fair value from warrant liability to additional paid-in capital. Changes in fair value of $0.1 million, $0.1 million, and $4.1 million were recognized for warrants exercised during the years ended December 31, 2021, 2020 and 2019, respectively.

Share-Based Compensation

12 Months Ended

Dec. 31, 2021

Share-based Payment Arrangement [Abstract]

Share-Based Compensation

Share-based compensation includes stock options, service-based RSUs and performance and service based RSUs granted under our 2012 Stock Incentive Plan (2012 Plan) and our Amended and Restated 2014 Omnibus Incentive Plan (2014 Plan, and together with the 2012 Plan, the Stock Plans).

The 2012 Plan was approved by the Board on April 16, 2012 and authorized 5.5 million shares of common stock to be reserved for issuance, with limits of 3.85 million shares available for stock option issuance and 1.65 million shares available for RSU issuance. Options granted under the 2012 Plan are non-qualified stock options and may be granted to employees, directors and other key persons. The exercise price per share for options covered by the 2012 Plan is determined by the Board at the time of grant, but shall not be less than the fair market value of our common stock, defined as the closing price of our common stock, on the date of the grant. The term of the stock option grants is established by the Board, but no stock option shall be exercisable more than ten years after the date the stock option is granted. The vesting period of the stock option grants is also established by the Board at the time of grant and is generally a three-year period. Upon the exercise of stock options, we issue shares from the authorized, unissued share reserve.

The 2014 Plan was originally approved by our stockholders at our annual meeting on May 8, 2014 and authorized 4.0 million shares of common stock to be reserved for issuance. On May 11, 2017, our stockholders approved amendments to the 2014 Plan at our annual stockholder meeting, authorizing an additional 2.0 million shares of common stock for issuance, increasing the total shares of common stock reserved for issuance under the plan to 6.0 million with the full amount available to be issued as either RSUs or options. These shares may be either authorized but unissued shares or treasury shares.

For the years ended December 31, 2021, 2020 and 2019, we incurred $16.7 million, $11.1 million and $13.0 million, respectively, of expenses related to awards granted under our Stock Plans. We recognized gross income tax benefits of $3.5 million, $2.3 million and $2.7 million for the years ended December 31, 2021, 2020 and 2019, respectively.

A summary of option activity during the years ended December 31, 2021, 2020 and 2019, is as follows:


For the year ended December 31, 2021	Shares	Weighted Average Grant Date Fair Value per Share		Weighted Average Exercise Price
	(Shares in Thousands)
Options outstanding at December 31, 2020	1,493	$	5.02	$	13.59
Options granted	—	—		—
Options exercised	(122)	(4.43)		11.42
Options forfeited	—	—		—
Options expired	—	—		—
Options outstanding at December 31, 2021	1,371	$	5.07	$	13.78


For the year ended December 31, 2020	Shares	Weighted Average Grant Date Fair Value per Share		Weighted Average Exercise Price
	(Shares in Thousands)
Options outstanding at December 31, 2019	1,928	$	4.84	$	13.04
Options granted	—	—		—
Options exercised	(435)	4.21		11.17
Options forfeited	—	—		—
Options expired	—	—		—
Options outstanding at December 31, 2020	1,493	$	5.02	$	13.59


For the Year Ended December 31, 2019	Shares	Weighted Average Grant Date Fair Value per Share		Weighted Average Exercise Price
	(Shares in Thousands)
Options outstanding at December 31, 2018	2,882	$	4.24	$	11.42
Options granted	163	8.85		22.19
Options exercised	(1,117)	3.88		10.19
Options forfeited	—	—		—
Options expired	—	—		—
Options outstanding at December 31, 2019	1,928	$	4.84	$	13.04

As of December 31, 2021, there were 1.3 million fully vested and exercisable options. During the year ended December 31, 2021, 0.1 million options were exercised with an aggregate intrinsic value of $1.5 million.

The weighted average exercise price for fully vested and exercisable options outstanding as of December 31, 2021 was $13.51 and the weighted average remaining contractual life of such options was 3.95 years as of December 31, 2021. The aggregate intrinsic value of such fully vested and exercisable options was $11.1 million as of December 31, 2021.

As of December 31, 2021, there was $14 thousand of total unrecognized compensation cost related to non-vested stock options. The weighted-average period over which total remaining unrecognized compensation costs related to non-vested stock options will be recognized is 0.12 years.

No stock options were granted during the years ended December 31, 2021 and 2020. The estimated grant date fair value of stock options granted during the year ended December 31, 2019 was calculated using the Black-Scholes valuation model based on the following assumptions:


	For the year ended December 31, 2019
Expected life	6 years
Risk free interest rate	2.57	%
Dividend yield	—	%
Expected stock price volatility	36.8	%

Expected life - is the period of time over which the options granted are expected to remain outstanding giving consideration to vesting schedules, historical exercise and forfeiture patterns. We use the simplified method outlined in SEC Staff Accounting Bulletin No. 107 to estimate expected life for options granted during the period as sufficient historical exercise data is not available and the options meet the requirements set out in the Bulletin. Options granted have a maximum term of 10 years.

Risk-free interest rate - is the U.S. Treasury rate on the date of the grant having a term approximating the expected life of the option.

Dividend yield - is calculated by dividing the expected annual dividend by our stock price at the valuation date.

Expected price volatility - is a measure of the amount by which a price has fluctuated or is expected to fluctuate.

A summary of RSU activity during the years ended December 31, 2021, 2020 and 2019 is as follows:


For the year ended December 31, 2021	Shares	Weighted Average Grant Date Fair Value per Share
	(Shares in Thousands)
Non-vested restricted stock units at December 31, 2020	1,062	$	21.61
Restricted stock units granted	589	23.73
Restricted stock units vested	(536)	19.98
Restricted stock units forfeited	(40)	21.58
Non-vested restricted stock units at December 31, 2021	1,075	$	23.59


For the year ended December 31, 2020	Shares	Weighted Average Grant Date Fair Value per Share
	(Shares in Thousands)
Non-vested restricted stock units at December 31, 2019	1,202	$	18.67
Restricted stock units granted	646	22.67
Restricted stock units vested	(664)	17.68
Restricted stock units forfeited	(122)	19.55
Non-vested restricted stock units at December 31, 2020	1,062	$	21.61


For the Year Ended December 31, 2019	Shares	Weighted Average Grant Date Fair Value per Share
	(Shares in Thousands)
Non-vested restricted stock units at December 31, 2018	1,753	$	12.06
Restricted stock units granted	470	24.42
Restricted stock units vested	(970)	9.71
Restricted stock units forfeited	(51)	15.06
Non-vested restricted stock units at December 31, 2019	1,202	$	18.67

At December 31, 2021, we had 1.1 million granted and non-vested RSUs, consisting of 0.9 million RSUs that are subject to service condition vesting requirements and 0.2 million RSUs that are subject to performance and service condition vesting requirements. The total fair value of RSUs vested during the year ended December 31, 2021 was $10.7 million. The remaining weighted average contractual life of non-vested RSUs was 1.24 years. As of December 31, 2021 and 2020, there were $8.8 million of total unrecognized compensation costs related to non-vested RSUs. The weighted-average period over which total remaining unrecognized compensation costs related to non-vested RSUs outstanding at December 31, 2021 will be recognized is 1.25 years.

Non-vested RSUs subject to service condition vesting requirements vest over a period ranging from one to five years. Non-vested RSUs subject to performance and service condition vesting requirements vest over a three-year period, with the number of shares issued upon vesting based on the actual achievement of compound annual book value per share growth compared to a target established at the time of grant. The grant date fair value of non-vested RSUs is measured as the closing price of our common stock on the date of grant less the present value of anticipated dividends to be paid during the vesting period.

401(k) Savings Plan

We offer our employees a 401(k) Savings Plan (401(k) Plan) that qualifies as a deferred salary arrangement under Section 401(k) of the Internal Revenue Code (IRC). Under the 401(k) Plan, we match up to 100% of eligible employees' pre-tax contributions up to 5% of eligible compensation. During the years ended December 31, 2021, 2020 and 2019, we incurred approximately $2.0 million, $2.2 million and $2.5 million of expense related to our matching 401(k) Plan contributions, respectively.

Income Taxes

12 Months Ended

Dec. 31, 2021

Income Tax Disclosure [Abstract]

Income Taxes

We are a U.S. taxpayer and are subject to a statutory U.S. federal corporate income tax rate of 21%. NMIH files a consolidated U.S. federal and various state income tax returns on behalf of itself and its subsidiaries.

Total income tax expense consists of the following components:


	For the year ended December 31,
	2021		2020		2019
	(In Thousands)
Current	$	85	$	34	$	(386)
Deferred	65,510		46,506		45,082
Total income tax expense	$	65,595	$	46,540	$	44,696

For the years ended December 31, 2021, 2020 and 2019, we had income tax expenses of $65.6 million, $46.5 million,

and $44.7 million, respectively, including amounts related to current state income taxes and changes to our federal and state net deferred tax liability.

The following table presents a reconciliation between the federal statutory income tax rate and our effective income tax rate:


	For the year ended December 31,
	2021		2020		2019
Federal statutory income tax rate	21.0	%	21.0	%	21.0	%
State provision	0.5	%	0.5		0.5
Share-based and other compensation	0.6	%	0.1		(1.7)
Warrant gain/loss	—	%	(0.3)		0.9

Other	—	%	—		(0.1)
Effective income tax rate	22.1	%	21.3	%	20.6	%

The components of our net deferred tax asset are summarized as follows:


	As of December 31,
	2021		2020
Deferred tax asset	(In Thousands)
Net operating loss carry forwards	$	8,759	$	7,938
Share-based compensation	6,090		5,067
Unearned premium reserve	5,878		4,844
Accrued expenses	2,852		3,198



Other	1,067		1,592
Total gross deferred tax asset	24,646		22,639
Less: valuation allowance	(8,582)		(7,610)
Total deferred tax asset	16,064		15,029
Deferred tax liability
Contingency reserve	(157,919)		(91,429)
Deferred acquisition costs	(12,797)		(13,381)
Capitalized software	(7,286)		(5,569)
Unrealized gain on investments	(1,503)		(15,432)

Other	(734)		(1,804)
Total deferred tax liability	(180,239)		(127,615)
Net deferred income tax (liability)	$	(164,175)	$	(112,586)

As a mortgage guaranty insurance company, we are eligible to claim a tax deduction for our statutory contingency reserve balance, subject to certain limitations outlined under IRC Section 832(e), to the extent we acquire tax and loss bonds in an amount equal to the tax benefit derived from the claimed deduction, which is our intent.

During the years ended December 31, 2021, 2020 and 2019, we purchased $42.9 million, $38.8 million and $7.6 million, of tax and loss bonds, respectively. As a result, we had no current federal income tax provision for the years ended December 31, 2021, 2020 and 2019. As of December 31, 2021 and 2020, we held $89.2 million and $46.4 million of tax and loss bonds, respectively, in "Other assets" in our consolidated balance sheet.

At December 31, 2021, we had a federal net operating loss carryforward of $1.8 million which expires in varying amounts in 2030 and 2031, and state net operating loss carryforward of $132.4 million which expire in varying amounts from 2031 to 2042. Section 382 of the IRC imposes annual limitations on a corporation's ability to utilize its net operating loss carryforwards if it experiences an "ownership change." As a result of the acquisition of our insurance subsidiaries in 2012, $7.3 million of federal net operating losses were subject to annual limitations of $0.8 million through 2016, and $0.3 million,

thereafter, through 2028. Our federal net operating loss carryforward arises from this limitation and the constraint on our ability to utilize the net operating loss carryforward in full during the current period.

At December 31, 2021 and 2020, we recorded valuation allowances of $8.6 million and $7.6 million, respectively, against state net deferred tax assets that may not be realized in future periods. The valuation allowances for both years primarily relate to state net operating losses generated by NMIH, as NMIH operates at a loss and currently only generates revenue from its investment portfolio.

As of December 31, 2021 and 2020, we had zero reserves for unrecognized tax benefits as we have taken no material uncertain tax positions that would have required a reserve to be measured and recognized.

We file income tax returns with the U.S. federal government and various state jurisdictions that are subject to potential examination by tax authorities. We are not currently under examination by federal or state jurisdictions. Our U.S. federal income tax returns for 2018 and subsequent years, and state income tax returns for 2017 and subsequent years, remain open by statute.

- Definition

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 21
-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32857-109319

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 11.C)
-URI http://asc.fasb.org/extlink&oid=122134291&loc=d3e330215-122817

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 17
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32809-109319

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 6.I.5.Q1)
-URI http://asc.fasb.org/extlink&oid=122134291&loc=d3e330036-122817

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 14
-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32705-109319

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 270
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6424409&loc=d3e44925-109338

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-URI http://asc.fasb.org/topic&trid=2144680

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6424122&loc=d3e41874-109331

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(h)(2))
-URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

+ Details

Software and Equipment

12 Months Ended

Dec. 31, 2021

Property, Plant and Equipment [Abstract]

Software and Equipment

Software and equipment consist largely of capitalized software developed to support our mortgage insurance operations. Software and equipment, net of accumulated amortization and depreciation, as of December 31, 2021 and 2020, consists of the following:


	December 31, 2021		December 31, 2020
	(In Thousands)
Software	$	72,481	$	59,677
Equipment	9,654		9,123
Leasehold improvements	3,402		3,402
Subtotal	85,537		72,203
Accumulated amortization and depreciation	(53,490)		(42,538)
Software and equipment, net	$	32,047	$	29,665

Capitalized costs for software, equipment, and leasehold improvements during the years ended December 31, 2021, 2020 and 2019 were $13.6 million, $14.5 million, and $10.6 million, respectively. Amortization and depreciation expense for software, equipment, and leasehold improvements for the years ended December 31, 2021, 2020, and 2019 were $11.2 million, $9.9 million, and $9.3 million, respectively.

Intangible Assets and Goodwill

12 Months Ended

Dec. 31, 2021

Goodwill and Intangible Assets Disclosure [Abstract]

Intangible Assets and Goodwill

Intangible assets and goodwill consist of identifiable intangible assets and goodwill purchased in connection with the acquisition of our insurance subsidiaries. Intangible assets and goodwill as of both December 31, 2021 and 2020 were as follows:


	(In Thousands)		Expected Lives
Goodwill	$	3,244	Indefinite
State licenses	260		Indefinite
GSE applications	130		Indefinite
Total intangible assets and goodwill	$	3,634

We test goodwill and intangible assets for impairment annually or more frequently if we believe indicators of impairment exist. No impairments of indefinite-lived intangibles or goodwill were identified during the years ended December 31, 2021, 2020 and 2019.

Commitments and Contingencies

12 Months Ended

Dec. 31, 2021

Commitments and Contingencies Disclosure [Abstract]

Commitments and Contingencies

PMIERs

As an approved insurer, NMIC is subject to ongoing compliance with the PMIERs established by each of the GSEs (italicized terms have the same meaning that such terms have in the PMIERs, as described below). The PMIERs establish operational, business, remedial and financial requirements applicable to approved insurers. The PMIERs financial requirements

prescribe a risk-based methodology whereby the amount of assets required to be held against each insured loan is determined based on certain loan-level risk characteristics, such as FICO, vintage (year of origination), performing vs. non-performing (i.e., current vs. delinquent), LTV and other risk features. In general, higher quality loans carry lower charges.

Under the PMIERs, approved insurers must maintain available assets that equal or exceed minimum required assets, which is an amount equal to the greater of (i) $400 million or (ii) a total risk-based required asset amount. The risk-based required asset amount is a function of the risk profile of an approved insurer's RIF, assessed on a loan-by-loan basis against certain risk-based factors derived from tables set out in the PMIERs, which is then adjusted on an aggregate basis for reinsurance transactions approved by the GSEs, such as with respect to our ILN Transactions and QSR Transactions. The aggregate gross risk-based required asset amount for performing, primary insurance is subject to a floor of 5.6% of performing, primary adjusted RIF, and the risk-based required asset amount for pool insurance considers both factors in the PMIERs tables and the net remaining stop loss for each pool insurance policy.

By April 15th of each year, NMIC must certify it met all PMIERs requirements as of December 31st of the prior year. We certified to the GSEs by April 15, 2021, that NMIC was in full compliance with the PMIERs as of December 31, 2020. NMIC also has an ongoing obligation to immediately notify the GSEs in writing upon discovery of a failure to meet one or more of the PMIERs requirements. We continuously monitor NMIC's compliance with the PMIERs.

Leases

We have two operating lease agreements related to our corporate headquarters and a data center facility for which we recognized operating ROU assets and lease liabilities of $2.6 million and $2.9 million in "Other assets" and "Other liabilities," respectively, on our consolidated balance sheet as of December 31, 2021. As of December 31, 2020, we recognized operating ROU assets and lease liabilities of $4.6 million and $5.3 million, respectively. As of December 31, 2021 and 2020, we did not have any finance leases.

We did not enter any new operating leases or recognize any new ROU assets or lease liabilities during the years ended December 31, 2021 and 2020. ROU assets exchanged for new operating lease liabilities for the year ended December 31, 2019 were $8.1 million, primarily in connection with our initial adoption of ASU 2016-02, Leases (Topic 842).

The following table provides a summary of our ROU asset and lease liability assumptions as of December 31, 2021:


Weighted-average remaining lease term	1.2 years
Weighted-average discount rate	6.21	%

Cash paid on our operating leases for the years ended December 31, 2021, 2020 and 2019 was $2.6 million, $2.5 million and $2.5 million and lease expense incurred was $2.3 million, $2.3 million and $2.2 million during each respective period, reflecting the net benefit of incentives received at inception of the lease.

Future payments due under our existing operating leases as of December 31, 2021 are as follows:


Years ending December 31,	(In Thousands)
2022	$	2,574
2023	462


Total undiscounted lease payments	3,036
Less effects of discounting	(135)
Present value of lease payments	$	2,901

In January 2022 we modified the lease for our corporate headquarters, securing a reduction in pricing and incremental leasehold improvement concessions, reducing the square footage of leased space and extending the remaining term through March 2030. In connection with these changes we expect to record a net increase of approximately $9.0 million to both ROU assets and lease liabilities, in the first quarter of 2022. Future lease payments due at the time of modification are $15.9 million and supersede any future payments otherwise due under the previous lease for our corporate headquarters outstanding as of December 31, 2021.

Lease expense is recorded in underwriting and operating expenses on our consolidated statement of operations. Our operating leases have original terms that range from three to seven years. The existing and modified lease for our corporate

headquarters both include an option to renew for an additional five years at prevailing market rates at time of renewal. Such renewal option is not included in the calculation of future lease payments due under the existing lease as presented above.

Common Stock	12 Months Ended
Common Stock	Dec. 31, 2021
Equity [Abstract]
Common Stock	Common Stock As of December 31, 2021, we had 85.8 million outstanding shares of Class A common stock. Holders of our common stock have no preemptive or conversion rights or other subscription rights, and there are no redemption or sinking fund provisions applicable to the common stock. Each holder of our common stock is entitled to one vote per share on all matters to be voted upon by stockholders, and there are no cumulative voting rights. Holders of common stock are entitled to receive dividends ratably if any are declared. As of December 31, 2020, we had 85.2 million outstanding shares of Class A common stock. On June 8, 2020, we completed the sale of 15.9 million shares of common stock which generated proceeds of $219.7 million, net of underwriting discounts, commissions and other direct offering expenses.

- Definition

The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Subparagraph (b)
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=123467817&loc=SL123496171-112644

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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-URI http://asc.fasb.org/extlink&oid=123467817&loc=SL123496171-112644

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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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-Section 50
-Paragraph 18
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=123467817&loc=SL123496189-112644

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
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Reference 8: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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-URI http://asc.fasb.org/extlink&oid=123467817&loc=SL123496189-112644

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=123467817&loc=SL123496189-112644

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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-Paragraph 16
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123467817&loc=SL123496180-112644

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=123467817&loc=SL123496158-112644

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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+ Details

Regulatory Information

12 Months Ended

Dec. 31, 2021

Insurance [Abstract]

Regulatory Information

Statutory Requirements

Our insurance subsidiaries, NMIC and Re One, file financial statements in conformity with statutory accounting principles (SAP) prescribed or permitted by the Wisconsin OCI, NMIC's principal regulator. Prescribed SAP includes state laws, regulations and general administrative rules, as well as a variety of publications of the National Association of Insurance Commissioners (NAIC). The Wisconsin OCI recognizes only statutory accounting practices prescribed or permitted by the state of Wisconsin for determining and reporting the financial condition and results of operations of an insurance company and for determining its solvency under Wisconsin insurance laws.

The Wisconsin OCI has imposed a prescribed accounting practice for the treatment of statutory contingency reserves that differs from the treatment promulgated by the NAIC. Under Wisconsin OCI's prescribed practice mortgage guaranty insurers are required to reflect changes in their contingency reserves through statutory income. Such approach contrasts with the NAIC's treatment, which records changes to contingency reserves directly to unassigned funds. As a Wisconsin-domiciled insurer, NMIC's statutory net income reflects an expense associated with the change in its contingency reserve. While such treatment impacts NMIC's statutory net income, it does not have an effect on the company's statutory capital position.

NMIC and Re One's combined statutory net income (loss), statutory surplus, contingency reserve, statutory capital and risk-to-capital (RTC) ratios as of and for the years ended December 31, 2021, 2020 and 2019 were as follows:


	As of and for the year ended December 31,
	2021		2020		2019
	(In Thousands)
Statutory net income (loss)	$	37,950	$	(20,136)	$	15,233

Statutory surplus	899,476		894,331		449,602
Contingency reserve	1,036,639		768,324		531,825
Statutory capital (1)	1,936,115		1,662,655		981,427

Risk-to-capital (2)	11.6:1		11.7:1		15.8:1

(1) Represents the total of the statutory surplus and contingency reserve.

(2) Excludes Re One as of December 31, 2021 as it had no risk in force remaining following the termination and commutation of the reinsurance agreement with

NMIC.

Under applicable law in Wisconsin and 15 other states, mortgage insurers must maintain minimum amounts of statutory capital relative to RIF to continue writing new business. While formulations of minimum statutory capital may vary in each state,

the most common measure allows for a maximum permitted RTC ratio of 25:1. Wisconsin and certain other states, including California and Illinois, apply a substantially similar requirement referred to as minimum policyholders' position.

The NAIC formed a Mortgage Guaranty Insurance Working Group (the Working Group) in 2012 to discuss, develop and recommend changes to the regulatory oversight and solvency standards of the mortgage insurance industry, including changes to the Mortgage Guaranty Insurance Model Act (Model Act). The Working Group has proposed amendments to the Model Act that include, among other changes, the introduction of a risk-based capital model. If adopted by the NAIC, some or all of the 16 states that currently have minimum statutory capital requirements, and potentially others that do not, could enact a portion or all of the revised Model Act, including the loan-level capital model. Such risk-based capital model, if introduced and enacted at a state level, is not expected to replace maximum permitted RTC ratio or minimum policyholders' position as the determinant driver of mortgage insurer minimum statutory capital requirements; rather, it is expected that such enactment would introduce new, non-operative statutory disclosure requirements.

As of December 31, 2021, NMIC's performing primary RIF, net of reinsurance, was approximately $22.3 billion and its RTC ratio was 11.6:1. As of December 31, 2020, NMIC's performing primary RIF, net of reinsurance, was approximately $19.4 billion and its RTC ratio was 12.0:1.

Reinsurance

Prior to January 10, 2019, Ohio regulation limited the amount of risk a mortgage insurer was permitted to retain on a single loan to 25% of the borrower's indebtedness (after giving effect to third-party reinsurance) and, as a result, the portion of such insurance in excess of 25% was required to be reinsured. Ohio repealed this requirement for future periods beginning January 10, 2019. Several other states previously imposed similar coverage restrictions and repealed these measures prior to 2018. To comply with these previous state coverage limits, NMIC and Re One had a reinsurance agreement in place under which Re One provided reinsurance to NMIC on certain insured loans with coverage levels in excess of 25%, after giving effect to third-party reinsurance.

Effective October 1, 2021, the reinsurance agreement between NMIC and Re One was commuted and all ceded risk was transferred back to NMIC. In connection with the commutation, Re One paid $8.4 million of fees to NMIC to settle all outstanding reinsurance obligations. Following the commutation, NMIC will no longer cede any premiums or loss to Re One, and Re One has no risk in force or further obligation on future claims.

Dividend Restrictions

NMIH is not subject to any limitations on its ability to pay dividends except those generally applicable to corporations that are incorporated in Delaware. Delaware law provides that dividends are only payable out of a corporation's capital surplus or, subject to certain limitations, recent net profits.

NMIC and Re One are subject to certain capital and dividend rules and regulations prescribed by jurisdictions in which they are authorized to operate and the GSEs that may restrict their ability to pay dividends to NMIH. Under Wisconsin law, NMIC and Re One may pay dividends up to specified levels (i.e., "ordinary" dividends) with 30 days' prior notice to the Wisconsin OCI. Dividends in larger amounts (i.e.,"extraordinary" dividends), are subject to the Wisconsin OCI's prior approval. Under Wisconsin law, an extraordinary dividend is defined as any payment or distribution that together with other dividends and distributions made within the preceding twelve months exceeds the lesser of (i) 10% of the insurer's statutory policyholders' surplus as of the preceding December 31 or (ii) adjusted statutory net income for the twelve-month period ending the preceding December 31. NMIC has the capacity to pay aggregate ordinary dividends of $34.9 million to NMIH during the twelve-month period ending December 31, 2022.

Following the commutation of the reinsurance agreement between NMIC and Re One, Re One distributed $26.0 million to NMIH in the form of a $1.6 million ordinary dividend and a $24.4 million extraordinary dividend with prior approval of the WI OCI.

The Wisconsin OCI has approved the allocation of interest expense on the $400 million Notes and $250 million 2021 Revolving Credit Facility to NMIC, to the extent proceeds from such offering and facility are distributed to NMIC or used to repay, redeem or otherwise defease amounts raised by NMIC under prior credit arrangements that have previously been distributed to NMIC.

As an approved insurer under PMIERs, NMIC would generally be subject to prior GSE approval of its ability to pay dividends to NMIH if it failed to meet the financial requirements prescribed by PMIERs. In response to the COVID-19 pandemic, the GSEs issued temporary PMIERs guidance, effective for the period from June 30, 2020 to June 30, 2021, that requires approved insurers to secure approval from the GSEs prior to paying any dividends, even if the approved insurer otherwise satisfies the financial requirements prescribed by PMIERs. On June 30, 2021, the GSEs updated the temporary PMIERs guidance to permit approved insurers to pay dividends without securing prior approval if certain prescribed financial requirements are met during the period from July 1, 2021 to December 31, 2021. NMIC did not pay any dividends during the year ended December 31, 2021.

Quarterly Financial Data (Unaudited)

12 Months Ended

Dec. 31, 2021

Quarterly Financial Information Disclosure [Abstract]

Quarterly Financial Data (Unaudited)


	2021 Quarters								2021
	First		Second		Third		Fourth		Year
	(In Thousands, except per share data)

Net premiums earned	$	105,879	$	110,888	$	113,594	$	113,933	$	444,294
Net investment income	8,814		9,382		9,831		10,045		38,072
Net realized investment gains	—		12		3		714		729
Other revenues	501		483		613		380		1,977

Insurance claims and claim expenses (benefit)	4,962		4,640		3,204		(500)		12,305		(2)

Underwriting and operating expenses	34,065		34,725		34,669		38,843		142,303		(2)
Service expenses	591		481		787		650		2,509
Interest expense	7,915		7,922		7,930		8,029		31,796
Loss (gain) from change in fair value of warrant liability	205		(658)		—		(112)		(566)		(2)
Pre-tax income	67,456		73,655		77,451		78,162		296,725		(2)
Income tax expense	14,565		16,133		17,258		17,639		65,595
Net income	$	52,891	$	57,522	$	60,193	$	60,523	$	231,130	(2)

Basic earnings per share (1)	$	0.62	$	0.67	$	0.70	$	0.71	$	2.70
Diluted earnings per share (1)	$	0.61	$	0.65	$	0.69	$	0.69	$	2.65

Weighted average common shares outstanding - basic	85,317		85,647		85,721		85,757		85,620
Weighted average common shares outstanding - diluted	86,487		86,819		86,880		87,117		86,885

(1) Due to the use of weighted average shares outstanding when calculating EPS, the sum of quarterly per share data may not equal the per share data for the year.

(2) May not foot by summing up the quarterly results due to rounding.


	2020 Quarters								2020
	First		Second		Third		Fourth		Year
	(In Thousands, except per share data)

Net premiums earned	$	98,717	$	98,944	$	98,802	$	100,709	$	397,172
Net investment income	8,104		7,070		8,337		8,386		31,897
Net realized investment (losses) gains	(72)		711		(4)		295		930
Other revenues	900		1,223		648		513		3,284

Insurance claims and claim expenses	5,697		34,334		15,667		3,549		59,247
Underwriting and operating expenses	32,277		30,370		33,969		34,994		131,610
Service expenses	734		1,090		557		459		2,840
Interest expense	2,744		5,941		7,796		7,906		24,387
(Gain) loss from change in fair value of warrant liability	(5,959)		1,236		437		1,379		(2,907)
Pre-tax income	72,156		34,977		49,357		61,616		218,106
Income tax expense	13,885		8,129		11,178		13,348		46,540
Net income	$	58,271	$	26,848	$	38,179	$	48,268	$	171,566

Basic earnings per share (1)	$	0.85	$	0.36	$	0.45	$	0.57	$	2.20
Diluted earnings per share (1)	$	0.74	$	0.36	$	0.45	$	0.56	$	2.13

Weighted average common shares outstanding - basic	68,563		73,617		84,805		84,956		78,023
Weighted average common shares outstanding - diluted	70,401		74,174		85,599		86,250		79,263

(1) Due to the use of weighted average shares outstanding when calculating EPS, the sum of quarterly per share data may not equal the per share data for the year.

Subsequent Event	12 Months Ended
Subsequent Event	Dec. 31, 2021
Subsequent Events [Abstract]
Subsequent Event	Subsequent EventOn February 10, 2022, the Board of Directors has approved a $125 million share repurchase program through December 31, 2023, that enables the company to repurchase its common stock. The authorization provides NMI the flexibility to repurchase shares from time to time in the open market or in privately negotiated transactions, based on market and business conditions, stock price and other factors.

SCHEDULE I - SUMMARY OF INVESTMENTS - OTHER THAN INVESTMENTS IN RELATED PARTIES

12 Months Ended

Dec. 31, 2021

SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Abstract]

Summary of Investments - Other than Investments in Related Parties


December 31, 2021	Amortized Cost		Fair Value		Amount Reflected on Balance Sheet
	(In Thousands)
U.S. Treasury securities and obligations of U.S. government agencies	$	29,443	$	30,424	$	30,424
Municipal debt securities	553,793		554,078		554,078
Corporate debt securities	1,388,204		1,393,830		1,393,830
Asset-backed securities	96,324		96,581		96,581
Total bonds	2,067,764		2,074,913		2,074,913

Short-term investments	11,009		11,018		11,018
Total investments	$	2,078,773	$	2,085,931	$	2,085,931

SCHEDULE II - FINANCIAL INFORMATION OF REGISTRANT- PARENT COMPANY ONLY

12 Months Ended

Dec. 31, 2021

Condensed Financial Information Disclosure [Abstract]

Financial Information of Registrant Parent Company Only


	December 31, 2021		December 31, 2020
	(In Thousands, except for share data)
Assets
Fixed maturities, available-for-sale, at fair value	$	84,854	$	52,867
Cash and cash equivalents	21,181		19,146
Investment in subsidiaries, at equity in net assets	1,951,124		1,724,360
Accrued investment income	367		263
Prepaid expenses	2,983		2,912
Due from affiliates, net	86,366		76,892
Software and equipment, net	32,047		29,665

Other assets	4,251		5,676
Total assets	$	2,183,173	$	1,911,781
Liabilities
Debt	$	394,623	$	393,301
Accounts payable and accrued expenses	42,246		30,802
Warrant liability, at fair value	2,363		4,409
Deferred tax liability, net	175,254		108,424
Other liabilities	2,901		5,254
Total liabilities	617,387		542,190

Shareholders' equity
Common stock - class A shares, $0.01 par value; 85,792,849 and 85,163,039 shares issued and outstanding as of December 31, 2021 and December 31, 2020, respectively (250,000,000 shares authorized)	858		852
Additional paid-in capital	955,302		937,872
Accumulated other comprehensive income, net of tax	1,485		53,856
Retained earnings	608,141		377,011
Total shareholders' equity	1,565,786		1,369,591
Total liabilities and shareholders' equity	$	2,183,173	$	1,911,781


	For the year ended December 31,
	2021		2020		2019
	(In Thousands)
Revenues
Net investment income	$	327	$	398	$	1,124
Net realized investment gains	10		23		1
Total revenues	337		421		1,125

Expenses
Other operating expenses	8,264		9,262		11,714
Interest expense	68		—		—
(Gain) loss from change in fair value of warrant liability	(566)		(2,907)		8,657
Total expenses	7,766		6,355		20,371

Equity in net income of subsidiaries	303,970		217,134		226,480

Income before income taxes	296,541		211,200		207,234
Income tax expense	65,411		39,634		35,277
Net income	$	231,130	$	171,566	$	171,957

Other comprehensive (loss) income, net of tax:
Unrealized (losses) gains in accumulated other comprehensive (loss) income, net of tax (benefit) expense of $(95), $25, and $82 for each of the years in the three-year period ended December 31, 2021, respectively	(357)		94		308
Reclassification adjustment for gains included in net income, net of tax expense of $2, $5 and $0 for each of the years in the three-year period ended December 31, 2021, respectively	(8)		(18)		—
Equity in other comprehensive (loss) income of subsidiaries	(52,006)		36,492		31,812
Other comprehensive (loss) income, net of tax	(52,371)		36,568		32,120
Comprehensive income	$	178,759	$	208,134	$	204,077


	For the year ended December 31,
	2021		2020		2019
Cash flows from operating activities	(In Thousands)
Net income	$	231,130	$	171,566	$	171,957
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
(Gain) loss from change in fair value of warrant liability	(566)		(2,907)		8,657
Net realized investment gains	(10)		(23)		(1)
Depreciation and amortization	801		807		286
Amortization of debt discount and debt issuance costs	1,861		4,036		1,011
Deferred income taxes	66,941		45,483		44,030
Share-based compensation expense	16,678		11,115		13,031
Changes in operating assets and liabilities:
Investment in subsidiaries, at equity in net assets	(302,165)		(217,134)		(226,480)
Accrued investment income	(104)		(44)		(3)
Receivable from affiliates	(9,474)		(14,651)		(20,902)
Prepaid expenses	(71)		420		(409)
Other assets	(425)		(336)		165
Accounts payable and accrued expenses	10,068		4,592		(1,640)
Net cash provided by provided by (used in) operating activities	14,664		2,924		(10,298)
Cash flows from investing activities
Capitalization of subsidiaries	(800)		(445,448)		(800)
Purchase of short-term investments	(10,640)		(19,897)		(104,192)
Purchase of fixed-maturity investments, available-for-sale	(2,797)		(53,504)		(2,186)
Proceeds from maturity of short-term investments	—		41,228		111,539
Proceeds from redemptions, maturities and sale of fixed-maturity investments, available-for-sale	4,464		20,241		5,877
Software and equipment	(1,026)		(2,633)		(854)
Net cash (used in) provided by investing activities	(10,799)		(460,013)		9,384
Cash flows from financing activities
Proceeds from issuance of common stock related to public offering, net of issuance costs	—		219,687		—
Proceeds from issuance of common stock related to employee equity plans	4,201		8,871		21,748
Proceeds from issuance of common stock related to warrant exercises	503		—		—
Taxes paid related to net share settlement of equity awards	(5,426)		(8,961)		(18,248)
Proceeds from senior secured notes	—		400,000		—
Repayments of term loan	—		(147,750)		(1,500)
Payments of debt issuance costs	(1,108)		(9,043)		—
Net cash provided by financing activities	(1,830)		462,804		2,000

Net increase in cash, cash equivalents and restricted cash	2,035		5,715		1,086
Cash, cash equivalents and restricted cash, beginning of period	19,146		13,431		12,345
Cash, cash equivalents and restricted cash, end of period	$	21,181	$	19,146	$	13,431

Note A

The NMI Holdings, Inc. (Parent Company) financial statements represent the stand-alone financial statements of the Parent Company. These financial statements have been prepared on the same basis and using the same accounting policies as described in the consolidated financial statements included herein. Refer to the Parent Company's consolidated financial statements for additional information.

Note B

NMIC and Re One are subject to certain capital and dividend rules and regulations prescribed by jurisdictions in which they are authorized to operate and the GSEs that may restrict their ability to pay dividends to NMIH. Under Wisconsin law, NMIC and Re One may pay dividends up to specified levels (i.e., "ordinary" dividends) with 30 days' prior notice to the Wisconsin OCI. Dividends in larger amounts (i.e.,"extraordinary" dividends), are subject to the Wisconsin OCI's prior approval. Under Wisconsin law, an extraordinary dividend is defined as any payment or distribution that together with other dividends and distributions made within the preceding twelve months exceeds the lesser of (i) 10% of the insurer's statutory policyholders' surplus as of the preceding December 31 or (ii) adjusted statutory net income for the twelve-month period ending the preceding December 31. During the year ended December 31, 2021, Re One distributed $26.0 million to NMIH in the form of a $1.6 million ordinary dividend and a $24.4 million extraordinary dividend. NMIC has the capacity to pay aggregate ordinary dividends of $34.9 million to NMIH during the twelve-month period ending December 31, 2022.

The remaining net assets from dividend capacity are considered restricted. As of December 31, 2021, the amount of restricted net assets held by our consolidated insurance subsidiaries, which represents our equity investment in those insurance subsidiaries less their aggregate dividend capacity, totaled $2.0 billion, compared to $1.7 billion as of December 31, 2020.

Note C

The Parent Company provides certain services to its subsidiaries. The Parent Company allocates to its subsidiaries corporate expense it incurs in the capacity of supporting those subsidiaries, based on either an allocated percentage of time spent or internally allocated capital. Total operating expenses allocated to subsidiaries for each of the years in the three year period ended December 31, 2021 were $149.4 million, $152.9 million and $117.1 million, respectively. Amounts charged to the subsidiaries for operating expenses are based on actual cost, without any mark-up. The Parent Company considers these charges fair and reasonable. The subsidiaries reimburse the Parent Company for these costs in a timely manner, which has the impact of improving the cash flows of the Parent Company.

SCHEDULE IV - FINANCIAL INFORMATION OF REGISTRANT REINSURANCE

12 Months Ended

Dec. 31, 2021

SEC Schedule, 12-17, Insurance Companies, Reinsurance [Abstract]

Financial Information of Registrant Reinsurance


	Gross Amount		Ceded to Other Companies		Assumed from Other Companies		Net Amount		Percentage of Amount Assumed to Net
For the years ended December 31,	(In thousands)
2021	$	536,630	$	92,336	$	—	$	444,294	—	%
2020	472,998		75,826		—		397,172		—	%
2019	398,303		53,288		—		345,015		—	%

Summary of Accounting Principles (Policies)	12 Months Ended
Summary of Accounting Principles (Policies)	Dec. 31, 2021
Accounting Policies [Abstract]
Basis of Presentation	Basis of PresentationThe accompanying consolidated financial statements include the results of NMIH and its wholly-owned subsidiaries. All inter-company transactions have been eliminated. These financial statements have been prepared in accordance with accounting principles generally accepted in the U.S. (GAAP) and our accounts are maintained in US dollars. The preparation of financial statements in accordance with GAAP requires management to make estimates and assumptions that affect reported amounts of assets and liabilities, as well as disclosure of contingent assets and liabilities as of the balance sheet date. Estimates also affect the reported amounts of income and expenses for the reporting period. Actual results could differ from those estimates.
Use of Estimates	Use of Estimates We use accounting principles and methods that conform to GAAP. We are required to apply significant judgment and make material estimates in the preparation of our financial statements and with regard to various accounting, reporting and disclosure matters. Assumptions and estimates are required to apply these principles where actual measurement is not possible or practical.
Insurance Premium Revenue Recognition	Insurance Premium Revenue Recognition Premiums for primary mortgage insurance policies may be paid in a single payment at origination (single premium), on a monthly installment basis (monthly premium) or on an annual installment basis (annual premium), with such election and payment type fixed at policy inception. Premiums written at origination for single premium policies are initially deferred as unearned premiums and amortized into earnings over the estimated policy life, in accordance with the anticipated expiration of risk. Monthly premiums are recognized as revenue in the month billed and when the coverage is effective. Annual premiums are initially deferred and earned on a straight-line basis over the year of coverage. Upon cancellation of a policy, all remaining non-refundable deferred and unearned premium is immediately earned, and any refundable deferred and unearned premium is returned to the policyholder and recorded as a reduction to written premium and unearned premium reserve in the period paid. Premiums written on pool transactions are earned over the period that coverage is provided.
Reserve for Insurance Claims and Claims Expenses	Reserves for Insurance Claims and Claim Expenses We establish reserves for claims based on our best estimate of the ultimate claim costs for defaulted loans using the general principles contained in ASC 944, Financial Services - Insurance (ASC 944). A loan is considered to be in "default" as of the payment date at which a borrower has missed the preceding two or more consecutive monthly payments. We establish reserves for loans that have been reported to us in default by servicers, referred to as case reserves, and additional loans that we estimate (based on actuarial review and other factors) to be in default that have not yet been reported to us by servicers, referred to as incurred but not reported (IBNR) reserves. We also establish reserves for claim expenses, which represent the estimated cost of the claim administration process, including legal and other fees, as well as other general expenses of administering the claim settlement process. Claim expense reserves are either allocated (i.e., associated with a specific claim) or unallocated (i.e., not associated with a specific claim). The establishment of claims and claim expense reserves is subject to inherent uncertainty and requires significant judgment by management. Reserves are established by estimating the number of loans in default that will result in a claim payment, which is referred to as claim frequency, and the amount of claim payment expected to be paid on each such loan in default, which is referred to as claim severity. Claim frequency and severity estimates are established based on historical observed experience regarding certain loan factors, such as age of the default, size of the loan and loan-to-value (LTV) ratios, and are strongly influenced by assumptions about the path of certain economic factors, such as house price appreciation, trends in unemployment and mortgage rates. We consider the appropriateness of such inputs at each fiscal quarter and conduct an actuarial review annually to evaluate and, if necessary, update these assumptions.
Investments	Investments We have designated our investment portfolio as available-for-sale and report our invested assets at fair value. Unrealized gains and losses in the portfolio, net of related tax expense or benefit, are recognized as a component of accumulated other comprehensive income (AOCI) in shareholders' equity. We measure fair value and classify invested assets in a hierarchy for disclosure purposes consisting of three "levels" based on the observability of inputs available in the marketplace used to measure fair value. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets (Level 1 measurements) and the lowest priority to unobservable inputs (Level 3 measurements). See Note 4, "Fair Value of Financial Instruments" for further discussion. Purchases and sales of investments are recorded on a trade date basis. Net investment income is recognized when earned, and includes interest and dividend income together with amortization of market premiums and discounts using the effective yield method, and is net of investment management fees and other investment related expenses. For asset-backed securities and any other holdings for which there is a prepayment risk, prepayment assumptions are evaluated and revised as necessary. Any adjustments required due to changes in effective yields and prepayment assumptions are recognized on a prospective basis. We recognize an impairment on a security through the consolidated statement of operations and comprehensive income if (i) we intend to sell the impaired security; or (ii) it is more likely than not that we will be required to sell the impaired security prior to recovery of its amortized cost basis. If a sale is intended or likely to be required, we write down the amortized cost basis of the security to fair value and recognize the full amount of the impairment through the statement of operations as a "Realized Investment Loss." For securities in an unrealized loss position where a sale is not intended or likely to be required, we further assess if the decline in fair value below amortized cost is driven by a credit related impairment, considering several items including, but not limited to: •the severity of the decline in fair value; •the financial condition of the issuer; •the failure of the issuer to make scheduled interest or principal payments; •recent rating downgrades of the applicable security or issuer by one or more nationally recognized statistical ratings organization; and •other adverse conditions related to or impacting the security or issuer. To the extent we determine that a security impairment is credit-related, an impairment loss is recognized through the statement of operations as a provision for credit loss expense, and presented as a "Realized Investment Loss." We recognize an allowance for credit losses for the difference between the amortized cost and present value of future expected cash flows, limited by the amount the fair value of the security is below its amortized cost. Subsequent changes (favorable and unfavorable) in credit losses are recognized through the statement of operations as a provision for or a reversal of credit loss expense, and presented as a "Realized Investment Gain or Loss." The portion of a security impairment attributed to other non-credit related factors is recognized in other comprehensive income, net of taxes. We have elected to present accrued interest receivable separately from available for sale securities on our consolidated balance sheet. Accrued interest receivable was $11.9 million as of December 31, 2021 and is included in "Accrued Investment Income." We have elected not to measure an allowance for credit losses for accrued interest receivable on available for sale securities. Accrued interest for available for sale securities is written off against interest income when the receivable has aged 90 days past due. We did not write off any accrued interest receivable during the years ended December 31, 2021, 2020 or 2019. We consider items such as commercial paper with original maturities of 90 days or less to be short-term investments.
Deferred Policy Acquisition Costs (DAC)	Deferred Policy Acquisition Costs (DAC)Costs directly associated with the successful acquisition of mortgage insurance policies, consisting of certain selling expenses and other policy issuance and underwriting expenses, are initially deferred and reported as DAC. DAC is reviewed periodically to determine that it does not exceed recoverable amounts. DAC is amortized to expense in proportion to estimated gross profits over the life of the associated policies. We revise the rate of amortization to reflect actual experience and any changes to persistency or loss development.
Premium Deficiency Reserves	Premium Deficiency ReservesWe consider whether a premium deficiency exists and premium deficiency reserve is required at each fiscal quarter using best estimate assumptions as of the testing date. Per ASC 944, a premium deficiency reserve shall be recognized if the sum of expected claim costs and claim adjustment expenses, expected dividends to policyholders, unamortized acquisition costs and maintenance costs exceeds future premiums, existing reserves and anticipated investment income.
Reinsurance	Reinsurance We account for premiums, claims and claim expenses that are ceded to reinsurers on basis consistent with that which we use to account for the original policies we issue and pursuant to the terms of our reinsurance contracts. We account for premiums ceded or otherwise paid to reinsurers as a reduction to premium revenue. NMIC entered into quota share reinsurance treaties effective September 1, 2016 (the 2016 QSR Transaction), January 1, 2018 (the 2018 QSR Transaction), April 1, 2020 (the 2020 QSR Transaction), January 1, 2021 (the 2021 QSR Transaction), October 1, 2021 (the 2022 QSR Transaction), and effective January 1, 2023 (the 2023 QSR Transaction), which we refer to collectively as the QSR Transactions. We earn profit and ceding commissions in connection with the QSR Transactions (see Note 6, "Reinsurance"). Profit commissions represent a percentage of the profits recognized by reinsurers that are returned to us, based on the level of claims and claim expenses that we cede. We recognize any profit commissions we earn as an increase to premium revenue. Ceding commissions are calculated as a percentage of ceded written premiums under the 2016 QSR Transaction and as a percentage of ceded earned premiums under the 2018, 2020, 2021, 2022, and 2023 QSR Transactions, and are intended to cover our costs of acquiring and servicing direct policies. We recognize any ceding commissions generated under the QSR Transactions in a manner consistent with our recognition of earnings on the underlying reinsured policies. We account for ceding commissions earned as a reduction to underwriting and operating expenses. Under the QSR Transactions, we cede a portion of claims and claim expenses and reserves to our reinsurers, and account for such ceded reserves as "Reinsurance Recoverables" on the consolidated balance sheets and such ceded expenses as reductions to claims and claim expenses on the consolidated statements of operations. As of December 31, 2021, we had $20.3 million of reinsurance recoverables under the QSR Transactions. We remain directly liable for all claim payments if we are unable to collect the recoverables due from our reinsurers and, as such, we actively monitor and manage our counterparty credit exposure to our reinsurance providers. We establish an allowance for expected credit loss against our reinsurance recoverables if we do not expect to recover amounts due from one or more of our reinsurance counterparties, and report our reinsurance recoverables net of such allowance, if any. We actively monitor the counterparty credit profiles of our reinsurers and each is required to partially collateralize its obligations under the terms of our QSR Transactions. The allowance for credit loss established with respect to our reinsurance recoverables was deemed immaterial as of December 31, 2021 and 2020.
Income Taxes	Income Taxes We account for income taxes using the liability method in accordance with ASC Topic 740, Income Taxes. The liability method measures the expected future tax effects of temporary differences at the enacted tax rates applicable for the period in which the deferred asset or liability is expected to be realized or settled. Temporary differences are differences between the tax basis of an asset or liability and its reported amount in the consolidated financial statements that would result in future increases or decreases in taxes owed on a cash basis compared to amounts already recognized as tax expense in the consolidated statement of operations.
Warrants	Warrants We account for warrants to purchase our common shares in accordance with ASC 470-20, Debt with Conversion and Other Options and ASC 815-40 Derivatives and Hedging - Contracts in Entity's Own Equity. Our outstanding warrants may be settled through either (i) physical settlement method, or (ii) cashless exercise, where the number of shares issued upon exercise of the warrants is reduced to cover the cost of the exercise in lieu of the holder remitting a cash payment for the exercise price. The warrants expire and are not exercisable after the 10th anniversary of the date issued. The number of warrants and exercise price are subject to anti-dilution provisions whereby the number of warrants may be increased and their exercise price may be adjusted downward under certain circumstances. The anti-dilutive adjustments may be in excess of any dilution incurred by the warrant holders, and may be triggered by events that are not dilutive. As a result, the warrants are classified as a liability. We revalue the warrants at the end of each reporting period, and any change in fair value is reported in the statements of operations in the period in which the change occurred. We calculated the fair value of the warrants using a Black-Scholes option-pricing model in combination with a binomial model.
Share-Based Compensation	Share-Based Compensation We account for stock compensation in accordance with ASC 718, Compensation - Stock Compensation, which addresses accounting for share-based awards and recognition of compensation expense, measured using grant date fair value, over the requisite service or performance period of the award. Share-based compensation includes restricted stock units (RSUs) and stock option grants under our Stock Plans. We calculate the fair value of stock option grants using a Black-Scholes option pricing model, which takes into account various subjective assumptions. Key assumptions used in the model include the expected volatility of our stock price, dividend yield and the risk-free interest rate, as well as the expected option term, giving consideration to the contractual terms of any award. RSU grants may contain a service condition, or performance and service conditions. RSU grants are valued at our stock price on the date of grant less the present value of anticipated dividends. We account for stock option and RSU forfeitures as they occur.
Earnings per Share (EPS)	Earnings per Share (EPS) Basic earnings (loss) per share is based on the weighted-average number of common shares outstanding. Diluted earnings (loss) per share is based on the weighted-average number of common shares outstanding and common share equivalents that would be issuable upon the vesting of existing service based and certain performance and service based RSUs, and exercise of vested and unvested stock options and outstanding warrants. Basic EPS is based on the weighted average number of shares of common stock outstanding. Diluted EPS is based on the weighted average number of shares of common stock outstanding and common stock equivalents that would be issuable upon the vesting of service based and performance and service-based restricted stock units (RSUs), and the exercise of vested and unvested stock options and outstanding warrants. The number of shares issuable for RSUs subject to performance and service based vesting requirements are only included in diluted shares if the relevant performance measurement period has commenced and results during such period meet the necessary performance criteria. The following table reconciles the net income and the weighted average shares of common stock outstanding used in the computations of basic and diluted EPS of common stock
Cash and Cash Equivalents	Cash and Cash Equivalents We consider items such as certificates of deposit and money market funds with original maturities of 90 days or less to be cash equivalents.
Software and Equipment	Software and EquipmentWe capitalize certain costs associated with the development of internal-use software and equipment. Software and equipment are stated at cost, less accumulated amortization and depreciation. Amortization of software and depreciation of equipment commences at the beginning of the month following our placement of the assets into use. Amortization and depreciation are calculated on a straight-line basis over the estimated useful life of the respective assets, typically from three to five years, unless factors indicate a shorter useful life.
Leases	LeasesWe recognize right-of-use (ROU) assets and corresponding lease liabilities for our lease arrangements. Lease liabilities are established based on the estimated present value of lease payments over the relevant lease term. We estimate a discount rate for each lease based on our estimated incremental borrowing rate at the commencement date of the relevant lease. ROU assets are measured as the associated lease liability plus any direct costs incurred in connection with the initial establishment of the lease, less any lease incentives received.
Business Combinations, Goodwill and Intangible Assets	Business Combinations, Goodwill and Intangible Assets Goodwill represents the excess of the purchase price over the estimated fair value of net assets acquired from a business combination. In accordance with ASC 350, Intangibles - Goodwill and Other, we test goodwill for impairment during the third quarter each year, or more frequently if we believe indicators of impairment exist. We have not identified any impairments of goodwill through December 31, 2021. Our intangible assets consist of state licenses and Fannie Mae and Freddie Mac (collectively, the GSEs) applications which have indefinite lives. We test indefinite-lived intangible assets for impairment during the fourth quarter of each year or more frequently if we believe indicators of impairment exist.
Premiums Receivable	Premiums Receivable Premiums receivable consists of premiums due on our mortgage insurance policies. If a mortgage insurance premium is unpaid for more than 120 days, the associated receivable is written off against earned premium and the related insurance policy is canceled. We recognize an allowance for credit losses for premiums receivable based on credit losses expected to arise over the life of the receivable. Due to the nature of our insurance policies (a necessary precondition for access to mortgage credit for covered borrowers) and the short duration of the related receivables, we do not typically experience credit losses against our premium receivables and the allowance for credit loss established on premium receivables was deemed immaterial at December 31, 2021 or 2020. Premiums receivable may be written off prior to 120 days in the ordinary course of business for non-credit events including, but not limited to, the modification or refinancing of an underlying insured loan. We have established a reserve for premium write-offs based on historical experience; such reserve was $2.3 million and $1.6 million at December 31, 2021 and 2020, respectively.
Variable Interest Entities	Variable Interest Entities NMIC is a party to reinsurance agreements with Oaktown Re Ltd., Oaktown Re II Ltd., Oaktown Re III Ltd., Oaktown Re IV Ltd., Oaktown Re V Ltd., Oaktown Re VI Ltd., and Oaktown Re VII Ltd. (special purpose reinsurance entities collectively referred to as the Oaktown Re Vehicles) effective May 2, 2017, July 25, 2018, July 30, 2019, July 30, 2020, October 29, 2020, April 27, 2021, and October 26, 2021, respectively. At inception of the respective reinsurance agreements, we determined that each of the Oaktown Re Vehicles were variable interest entities (VIEs), as defined under GAAP Accounting Standards Codification (ASC) 810, because they did not have sufficient equity at risk to finance their respective activities. We evaluated the VIEs at inception to determine whether NMIC was the primary beneficiary under each deal and, if so, whether we were required to consolidate the assets and liabilities of each VIE. The primary beneficiary of a VIE is an enterprise that (1) has the power to direct the activities of the VIE, which most significantly impact its economic performance and (2) has significant economic exposure to the VIE, i.e., the obligation to absorb losses or receive benefits that could potentially be significant. The determination of whether an entity is the primary beneficiary of a VIE is complex and requires management judgment regarding determinative factors, including the expected results of the VIE and how those results are absorbed by beneficial interest holders, as well as which party has the power to direct activities that most significantly impact the performance of the VIE. We concluded that we are not the primary beneficiary of each VIE and, as such, we do not consolidate them in our consolidated financial statements.
Other Revenues	Other Revenues Other revenues represent underwriting fee revenue from our subsidiary, NMIS, which provides outsourced loan review services to mortgage loan originators. NMIS fees are earned and recognized as services are provided.
Recent Accounting Pronouncements	Recent Accounting Pronouncements - Adopted In December 2019, the Financial Accounting Standards Board (the FASB) issued ASU 2019-12, Simplifying the Accounting for Income Taxes (Topic 740). The update eliminates certain exceptions for recognizing deferred taxes for investments, performing intra-period allocations and calculating income taxes in interim periods. The ASU also includes guidance to reduce complexity in certain income tax areas, including recognizing deferred taxes for tax goodwill and allocating taxes to members of a consolidated group. We adopted this ASU on January 1, 2021 and determined it did not have a material impact on our consolidated financial statements. Recent Accounting Pronouncements - Not Yet Adopted In August 2018, the FASB issued ASU 2018-12, Targeted Improvements to the Accounting for Long-Duration Contracts (Topic 944). The update provides guidance to the existing recognition, measurement, presentation and disclosure requirements for long-duration contracts issued by an insurance entity. The FASB subsequently issued ASU 2019-09 in November 2019 and ASU 2020-11 in November 2020, which amended the effective date for this standard and provided transition relief to facilitate early application for long duration contracts. The standard will now take effect for public business entities for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2022. We are currently evaluating the impact the adoption of this ASU will have, if any, on our consolidated financial statements. In March 2020, the FASB issued ASU 2020-04, Reference Rate Reform (Topic 848). The update provides optional guidance to ease the potential burden in accounting for reference rate reform on financial reporting. Reference rate reform refers to the global transition away from referencing the London Interbank Offered Rate (LIBOR) in financial contracts, which is expected to be discontinued during a transition period from 2021 through 2023. The ASU includes optional expedients and exceptions for applying GAAP to contracts, hedging relationships and other transactions affected by reference rate reform if certain criteria are met. This standard may be elected and applied prospectively over time from March 12, 2020 through December 31, 2022 as reference rate reform activities occur. The adoption of, and future elections under, this ASU are not expected to have a material impact on our consolidated financial statements as the ASU will ease, if warranted, the requirements for accounting for the future effects of the rate reform. We continue to monitor the impact the discontinuance of LIBOR or another reference rate will have on our contracts and other transactions. In August 2020, the FASB issued ASU 2020-06, Debt—Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging— Contracts in Entity's Own Equity (Subtopic 815-40). The update simplifies the accounting for convertible instruments and contracts on an entity's own equity, including warrants, eliminating certain triggers for derivative accounting. We adopted this ASU on January 1, 2022 and determined it did not have a material impact on our consolidated financial statements, including our warrant liability.

Investments (Tables)

12 Months Ended

Dec. 31, 2021

Investments, Debt and Equity Securities [Abstract]

Schedule of fair values and gross unrealized gains and losses

Fair Values and Gross Unrealized Gains and Losses on Investments


	Amortized Cost		Gross Unrealized				Fair Value
			Gains		Losses
As of December 31, 2021	(In Thousands)
U.S. Treasury securities and obligations of U.S. government agencies	$	29,443	$	981	$	—	$	30,424
Municipal debt securities	553,793		5,689		(5,404)		554,078
Corporate debt securities	1,388,204		22,990		(17,364)		1,393,830
Asset-backed securities	96,324		684		(427)		96,581
Total bonds	2,067,764		30,344		(23,195)		2,074,913

Short-term investments	11,009		9		—		11,018
Total investments	$	2,078,773	$	30,353	$	(23,195)	$	2,085,931


	Amortized Cost		Gross Unrealized				Fair Value
			Gains		Losses
As of December 31, 2020	(In Thousands)
U.S. Treasury securities and obligations of U.S. government agencies	$	29,412	$	2,186	$	—	$	31,598
Municipal debt securities	407,323		14,027		(2)		421,348
Corporate debt securities	1,165,260		55,014		(483)		1,219,791
Asset-backed securities	128,471		2,736		(27)		131,180
Total bonds	1,730,466		73,963		(512)		1,803,917

Short-term investments	369		—		—		369
Total investments	$	1,730,835	$	73,963	$	(512)	$	1,804,286

Schedule of investments by industry group

The following table presents a breakdown of the fair value of our corporate debt securities by issuer industry group as of December 31, 2021 and 2020:


	December 31, 2021		December 31, 2020
Financial	38	%	37	%
Consumer	24		23
Communications	11		10
Utilities	10		11
Technology	9		10
Industrial	8		9
Total	100	%	100	%

Schedule of investments by maturity


As of December 31, 2021	Amortized Cost		Fair Value
	(In Thousands)
Due in one year or less	$	81,699	$	82,201
Due after one through five years	630,625		644,447
Due after five through ten years	1,215,224		1,207,997
Due after ten years	54,901		54,705
Asset-backed securities	96,324		96,581
Total investments	$	2,078,773	$	2,085,931


As of December 31, 2020	Amortized Cost		Fair Value
	(In Thousands)
Due in one year or less	$	57,429	$	57,949
Due after one through five years	507,444		536,520
Due after five through ten years	1,016,230		1,056,098
Due after ten years	21,261		22,539
Asset-backed securities	128,471		131,180
Total investments	$	1,730,835	$	1,804,286

Schedule of aging unrealized losses

For those securities in an unrealized loss position, the length of time the securities were in such a position is as follows:


	Less Than Twelve Months					Twelve Months or Greater					Total
	# of Securities	Fair Value		Unrealized Losses		# of Securities	Fair Value		Unrealized Losses		# of Securities	Fair Value		Unrealized Losses
As of December 31, 2021		(Dollars in Thousands)

Municipal debt securities	151	$	314,823	$	(4,959)	2	$	8,138	$	(445)	153	$	322,961	$	(5,404)
Corporate debt securities	114	653,488		(11,426)		20	146,003		(5,938)		134	799,491		(17,364)
Asset-backed securities	11	57,601		(357)		1	1,977		(70)		12	59,578		(427)
Total	276	$	1,025,912	$	(16,742)	23	$	156,118	$	(6,453)	299	$	1,182,030	$	(23,195)


	Less Than Twelve Months					Twelve Months or Greater					Total
	# of Securities	Fair Value		Unrealized Losses		# of Securities	Fair Value		Unrealized Losses		# of Securities	Fair Value		Unrealized Losses
As of December 31, 2020		(Dollars in Thousands)

Municipal debt securities	4	$	3,548	$	(2)	—	$	—	$	—	4	$	3,548	$	(2)
Corporate debt securities	9	40,081		(483)		1	33		—		10	40,114		(483)
Asset-backed securities	2	5,191		(19)		1	2,495		(8)		3	7,686		(27)
Total	15	$	48,820	$	(504)	2	$	2,528	$	(8)	17	$	51,348	$	(512)

Schedule of net investment income

The following table presents the components of net investment income:


	For the year ended December 31,
	2021		2020		2019
	(In Thousands)
Investment income	$	39,385	$	33,140	$	31,332
Investment expenses	(1,313)		(1,243)		(476)
Net investment income	$	38,072	$	31,897	$	30,856

Schedule of net realized investment gains (losses)

The following table presents the components of net realized investment gains:


	For the year ended December 31,
		2021		2020		2019
		(In Thousands)
Gross realized investment gains		$	729	$	5,572	$	561
Gross realized investment losses		—		(4,642)		(516)
Net realized investment gains		$	729	$	930	$	45

Fair Value of Financial Instruments (Tables)

12 Months Ended

Dec. 31, 2021

Fair Value Disclosures [Abstract]

Schedule of fair value measurements of financial instruments

The following tables present the level within the fair value hierarchy at which our financial instruments were measured:


	Fair Value Measurements Using
	Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Fair Value
As of December 31, 2021	(In Thousands)
U.S. Treasury securities and obligations of U.S. government agencies	$	30,424	$	—	$	—	$	30,424
Municipal debt securities	—		554,078		—		554,078
Corporate debt securities	—		1,393,830		—		1,393,830
Asset-backed securities	—		96,581		—		96,581

Cash, cash equivalents and short-term investments	87,664		—		—		87,664
Total assets	$	118,088	$	2,044,489	$	—	$	2,162,577
Warrant liability	—		—		2,363		2,363
Total liabilities	$	—	$	—	$	2,363	$	2,363


	Fair Value Measurements Using
	Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Fair Value
As of December 31, 2020	(In Thousands)
U.S. Treasury securities and obligations of U.S. government agencies	$	31,598	$	—	$	—	$	31,598
Municipal debt securities	—		421,348		—		421,348
Corporate debt securities	—		1,219,791		—		1,219,791
Asset-backed securities	—		131,180		—		131,180

Cash, cash equivalents and short-term investments	127,306		—		—		127,306
Total assets	$	158,904	$	1,772,319	$	—	$	1,931,223
Warrant liability	—		—		4,409		4,409
Total liabilities	$	—	$	—	$	4,409	$	4,409

Schedule of roll-forward of level 3 liabilities measured at fair value

The following table provides a roll-forward of Level 3 liabilities measured at fair value:


	For the year ended December 31,
Warrant Liability	2021		2020		2019
	(In Thousands)
Balance, January 1	$	4,409	$	7,641	$	7,296
Change in fair value of warrant liability included in earnings	(566)		(2,907)		8,657
Issuance of common stock on warrant exercise	(1,480)		(325)		(8,312)
Balance, December 31	$	2,363	$	4,409	$	7,641

Schedule of key inputs and assumptions in option-pricing model

The following table outlines the key inputs and assumptions used to calculate the fair value of the warrant liability in the Black-Scholes option-pricing model as of the dates indicated:


	As of December 31,
	2021			2020			2019
Common stock price	$	21.85		$	22.65		$	33.18
Risk free interest rate	0.07		%	0.11		%	1.59		%
Expected life	0.31 years			1.31 years			2.31 years
Expected volatility	26.3		%	83.7		%	41.4		%
Dividend yield	—		%	—		%	—		%

- Definition

Tabular disclosure of financial instruments measured at fair value, including those classified in shareholders' equity measured on a recurring or nonrecurring basis. Disclosures include, but are not limited to, fair value measurements recorded and the reasons for the measurements, level within the fair value hierarchy in which the fair value measurements are categorized and transfers between levels 1 and 2. Nonrecurring fair value measurements are those that are required or permitted in the statement of financial position in particular circumstances.

+ References + Details

Reinsurance (Tables)

12 Months Ended

Dec. 31, 2021

Reinsurance Disclosures [Abstract]

Schedule of effects of reinsurance agreements

The effect of our reinsurance agreements on premiums written and earned is as follows:


	For the year ended
	December 31, 2021		December 31, 2020		December 31, 2019
	(In Thousands)
Net premiums written
Direct	$	557,050	$	455,172	$	376,052
Ceded (1)	(88,539)		(66,528)		(43,400)
Net premiums written	$	468,511	$	388,644	$	332,652

Net premiums earned
Direct	$	536,630	$	472,998	$	398,303
Ceded (1)	(92,336)		(75,826)		(53,288)
Net premiums earned	$	444,294	$	397,172	$	345,015

(1) Net of profit commission.

The following table shows amounts related to the QSR Transactions:


	For the year ended
	December 31, 2021		December 31, 2020		December 31, 2019
	(In Thousands)
Ceded risk-in-force	$	8,194,604	$	5,543,969	$	5,137,249

Ceded premiums earned	(110,140)		(94,899)		(89,211)
Ceded claims and claim expenses	3,233		14,002		3,465

Ceding commission earned	23,473		18,526		17,652
Profit commission	59,104		41,902		50,513

Schedule of ILN transactions


($ values in thousands)	Inception Date	Covered Production	Initial Reinsurance Coverage	Current Reinsurance Coverage	Initial First Layer Retained Loss	Current First Layer Retained Loss (1)
2017 ILN Transaction	May 2, 2017	1/1/2013 - 12/31/2016	$211,320	$27,425	$126,793	$121,163
2018 ILN Transaction	July 25, 2018	1/1/2017 - 5/31/2018	264,545	158,489	125,312	122,569
2019 ILN Transaction	July 30, 2019	6/1/2018 - 6/30/2019	326,905	231,877	123,424	122,548
2020-1 ILN Transaction	July 30, 2020	7/1/2019 - 3/31/2020	322,076	49,879	169,514	169,488
2020-2 ILN Transaction	October 29, 2020	4/1/2020 - 9/30/2020 (2)	242,351	155,129	121,777	121,177
2021-1 ILN Transaction (5)	April 27, 2021	10/1/2020 - 3/31/2021 (3)	367,238	367,238	163,708	163,708
2021-2 ILN Transaction (5)	October 26, 2021	4/1/2021 - 9/30/2021 (4)	363,596	363,596	146,229	146,229

(2) Approximately 1% of the production covered by the 2020-2 ILN Transaction has coverage reporting dates between July 1, 2019 and March 31, 2020.

(3) Approximately 1% of the production covered by the 2021-1 ILN Transaction has coverage reporting dates between July 1, 2019 and September 30, 2020.

(4) Approximately 2% of the production covered by the 2021-2 ILN Transaction has coverage reporting dates between July 1, 2019 and March 31, 2021.

Reserves for Insurance Claims and Claim Expenses (Tables)

12 Months Ended

Dec. 31, 2021

Insurance [Abstract]

Schedule of reconciliation of liability for insurance claims and claims expenses

The following table provides a reconciliation of the beginning and ending gross reserve balances for primary insurance claims and claim expenses:


	For the year ended
	December 31, 2021		December 31, 2020		December 31, 2019
	(In Thousands)
Beginning balance	$	90,567	$	23,752	$	12,811
Less reinsurance recoverables (1)	(17,608)		(4,939)		(3,001)
Beginning balance, net of reinsurance recoverables	72,959		18,813		9,810

Add claims incurred:
Claims and claim expenses incurred:
Current year (2)	23,433		66,943		14,737
Prior years (3)	(11,128)		(7,696)		(2,230)
Total claims and claim expenses incurred	12,305		59,247		12,507

Less claims paid:
Claims and claim expenses paid:
Current year (2)	16		586		204
Prior years (3)	2,017		4,515		3,849
Reinsurance terminations (4)	—		—		(549)
Total claims and claim expenses paid	2,033		5,101		3,504

Reserve at end of period, net of reinsurance recoverables	83,231		72,959		18,813
Add reinsurance recoverables (1)	20,320		17,608		4,939
Ending balance	$	103,551	$	90,567	$	23,752

(1) Related to ceded losses recoverable under the QSR Transactions. See Note 6, "Reinsurance" for additional information.

Schedule of claims development data

The following tables provide claim development data by accident year and a reconciliation to the reserve for insurance claims and claim expenses:


	Cumulative Incurred Claims and Allocated Claims Adjustment Expenses, net of Reinsurance (1)																		As of December 31, 2021
Accident Year	2013		2014		2015		2016		2017		2018		2019		2020		2021		Total of IBNR		Defaults (2)
($ Values In Thousands)
2013	$	—	$	—	$	—	$	—	$	—	$	—	$	—	$	—	$	—	$	—	—
2014			83		34		4		4		4		4		4		4		—		—
2015					699		664		743		764		894		894		894		—		—
2016							2,394		1,568		1,790		1,934		1,936		1,930		4		3
2017									6,028		3,475		3,570		3,807		3,716		5		9
2018											7,779		5,271		4,709		4,533		56		47
2019													14,391		7,229		5,781		192		228
2020															65,769		56,154		4,112		2,547
2021																	22,847		362		3,393
															Total		$	95,859	$	4,731	6,227

(1) Amounts include case and IBNR reserves.

(2) Number of defaults outstanding as of December 31, 2021.


	Cumulative Paid Claims and Claims Adjustment Expenses, net of Reinsurance
Accident Year	2013		2014		2015		2016		2017		2018		2019		2020		2021
	(In Thousands)
2013	$	—	$	—	$	—	$	—	$	—	$	—	$	—	$	—	$	—
2014			—		4		4		4		4		4		4		4
2015					50		246		684		720		804		894		894
2016							171		890		1,596		1,826		1,827		1,877
2017									27		1,655		2,925		3,494		3,640
2018											130		1,981		3,537		3,780
2019													69		2,368		3,212
2020															586		1,320
2021																	16
															Total		$	14,743

Schedule of reconciliation of claims development to liability


Reconciliation of Disclosure of Incurred and Paid Claims Development to the Liability for Unpaid Claims and Claim Adjustment Expenses
(In Thousands)
	As of December 31, 2021
Cumulative Incurred Claims and Allocated Claims Adjustment Expenses, net of Reinsurance	$	95,859
Cumulative Paid Claims and Claims Adjustment Expenses, net of Reinsurance	14,743
Liabilities for unpaid claims and allocated claims adjustment expenses, net of reinsurance	81,116
Reinsurance recoverable on unpaid claims	20,320
Unallocated claims adjustment expenses	2,115
Total gross liability for unpaid claims and claim adjustment expenses	$	103,551

Schedule of historical claims duration

The following table shows the average percentage of claims and allocated claims adjustment expenses paid in the years following the incurrence of a claim:


	Average annual percentage payout of incurred claims and allocated claims adjustment expenses by age, net of reinsurance
	Year 1	Year 2	Year 3	Year 4	Year 5	Year 6	Year 7	Year 8
Claims duration disclosure	2%	32%	82%	93%	96%	99%	100%	100	%

Earnings per Share (Tables)

12 Months Ended

Dec. 31, 2021

Earnings Per Share [Abstract]

Schedule of earnings per share, basic and diluted


	For the year ended December 31,
		2021		2020		2019
		(In Thousands, except for per share data)
Net income		$	231,130	$	171,566	$	171,957
Basic weighted average shares outstanding		85,620		78,023		67,573
Basic earnings per share		$	2.70	$	2.20	$	2.54

Net income		$	231,130	$	171,566	$	171,957
Gain from change in fair value of warrant liability		(566)		(2,907)		—
Diluted net income		$	230,564	$	168,659	$	171,957

Basic weighted average shares outstanding		85,620		78,023		67,573
Dilutive effect of issuable shares		1,265		1,240		2,148
Diluted weighted average shares outstanding		86,885		79,263		69,721

Diluted earnings per share		$	2.65	$	2.13	$	2.47

Anti-dilutive shares		3		58		565

Share-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2021

Share-based Payment Arrangement [Abstract]

Schedule of stock option activity

A summary of option activity during the years ended December 31, 2021, 2020 and 2019, is as follows:


For the year ended December 31, 2021	Shares	Weighted Average Grant Date Fair Value per Share		Weighted Average Exercise Price
	(Shares in Thousands)
Options outstanding at December 31, 2020	1,493	$	5.02	$	13.59
Options granted	—	—		—
Options exercised	(122)	(4.43)		11.42
Options forfeited	—	—		—
Options expired	—	—		—
Options outstanding at December 31, 2021	1,371	$	5.07	$	13.78


For the year ended December 31, 2020	Shares	Weighted Average Grant Date Fair Value per Share		Weighted Average Exercise Price
	(Shares in Thousands)
Options outstanding at December 31, 2019	1,928	$	4.84	$	13.04
Options granted	—	—		—
Options exercised	(435)	4.21		11.17
Options forfeited	—	—		—
Options expired	—	—		—
Options outstanding at December 31, 2020	1,493	$	5.02	$	13.59


For the Year Ended December 31, 2019	Shares	Weighted Average Grant Date Fair Value per Share		Weighted Average Exercise Price
	(Shares in Thousands)
Options outstanding at December 31, 2018	2,882	$	4.24	$	11.42
Options granted	163	8.85		22.19
Options exercised	(1,117)	3.88		10.19
Options forfeited	—	—		—
Options expired	—	—		—
Options outstanding at December 31, 2019	1,928	$	4.84	$	13.04

Schedule of stock options valuation assumptions

The estimated grant date fair value of stock options granted during the year ended December 31, 2019 was calculated using the Black-Scholes valuation model based on the following assumptions:


	For the year ended December 31, 2019
Expected life	6 years
Risk free interest rate	2.57	%
Dividend yield	—	%
Expected stock price volatility	36.8	%

Schedule of restricted stock units activity

A summary of RSU activity during the years ended December 31, 2021, 2020 and 2019 is as follows:


For the year ended December 31, 2021	Shares	Weighted Average Grant Date Fair Value per Share
	(Shares in Thousands)
Non-vested restricted stock units at December 31, 2020	1,062	$	21.61
Restricted stock units granted	589	23.73
Restricted stock units vested	(536)	19.98
Restricted stock units forfeited	(40)	21.58
Non-vested restricted stock units at December 31, 2021	1,075	$	23.59


For the year ended December 31, 2020	Shares	Weighted Average Grant Date Fair Value per Share
	(Shares in Thousands)
Non-vested restricted stock units at December 31, 2019	1,202	$	18.67
Restricted stock units granted	646	22.67
Restricted stock units vested	(664)	17.68
Restricted stock units forfeited	(122)	19.55
Non-vested restricted stock units at December 31, 2020	1,062	$	21.61


For the Year Ended December 31, 2019	Shares	Weighted Average Grant Date Fair Value per Share
	(Shares in Thousands)
Non-vested restricted stock units at December 31, 2018	1,753	$	12.06
Restricted stock units granted	470	24.42
Restricted stock units vested	(970)	9.71
Restricted stock units forfeited	(51)	15.06
Non-vested restricted stock units at December 31, 2019	1,202	$	18.67

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2021

Income Tax Disclosure [Abstract]

Schedule of components of income tax expense (benefit)

Total income tax expense consists of the following components:


	For the year ended December 31,
	2021		2020		2019
	(In Thousands)
Current	$	85	$	34	$	(386)
Deferred	65,510		46,506		45,082
Total income tax expense	$	65,595	$	46,540	$	44,696

Schedule of effective income tax rate reconciliation

The following table presents a reconciliation between the federal statutory income tax rate and our effective income tax rate:


	For the year ended December 31,
	2021		2020		2019
Federal statutory income tax rate	21.0	%	21.0	%	21.0	%
State provision	0.5	%	0.5		0.5
Share-based and other compensation	0.6	%	0.1		(1.7)
Warrant gain/loss	—	%	(0.3)		0.9

Other	—	%	—		(0.1)
Effective income tax rate	22.1	%	21.3	%	20.6	%

Schedule of net deferred tax asset

The components of our net deferred tax asset are summarized as follows:


	As of December 31,
	2021		2020
Deferred tax asset	(In Thousands)
Net operating loss carry forwards	$	8,759	$	7,938
Share-based compensation	6,090		5,067
Unearned premium reserve	5,878		4,844
Accrued expenses	2,852		3,198



Other	1,067		1,592
Total gross deferred tax asset	24,646		22,639
Less: valuation allowance	(8,582)		(7,610)
Total deferred tax asset	16,064		15,029
Deferred tax liability
Contingency reserve	(157,919)		(91,429)
Deferred acquisition costs	(12,797)		(13,381)
Capitalized software	(7,286)		(5,569)
Unrealized gain on investments	(1,503)		(15,432)

Other	(734)		(1,804)
Total deferred tax liability	(180,239)		(127,615)
Net deferred income tax (liability)	$	(164,175)	$	(112,586)

Software and Equipment (Tables)

12 Months Ended

Dec. 31, 2021

Property, Plant and Equipment [Abstract]

Schedule of equipment and software

Software and equipment, net of accumulated amortization and depreciation, as of December 31, 2021 and 2020, consists of the following:


	December 31, 2021		December 31, 2020
	(In Thousands)
Software	$	72,481	$	59,677
Equipment	9,654		9,123
Leasehold improvements	3,402		3,402
Subtotal	85,537		72,203
Accumulated amortization and depreciation	(53,490)		(42,538)
Software and equipment, net	$	32,047	$	29,665

Intangible Assets and Goodwill (Tables)

12 Months Ended

Dec. 31, 2021

Goodwill and Intangible Assets Disclosure [Abstract]

Schedule of identifiable intangible assets and goodwill


	(In Thousands)		Expected Lives
Goodwill	$	3,244	Indefinite
State licenses	260		Indefinite
GSE applications	130		Indefinite
Total intangible assets and goodwill	$	3,634

Commitments and Contingencies (Tables)

12 Months Ended

Dec. 31, 2021

Commitments and Contingencies Disclosure [Abstract]

Summary of right-of-use asset and lease liability activity and assumptions

The following table provides a summary of our ROU asset and lease liability assumptions as of December 31, 2021:


Weighted-average remaining lease term	1.2 years
Weighted-average discount rate	6.21	%

Schedule of future payments due under operating leases

Future payments due under our existing operating leases as of December 31, 2021 are as follows:


Years ending December 31,	(In Thousands)
2022	$	2,574
2023	462


Total undiscounted lease payments	3,036
Less effects of discounting	(135)
Present value of lease payments	$	2,901

Regulatory Information (Tables)

12 Months Ended

Dec. 31, 2021

Insurance [Abstract]

Schedule of statutory net income (loss), surplus, contingency reserve and risk-to-capital ratio


	As of and for the year ended December 31,
	2021		2020		2019
	(In Thousands)
Statutory net income (loss)	$	37,950	$	(20,136)	$	15,233

Statutory surplus	899,476		894,331		449,602
Contingency reserve	1,036,639		768,324		531,825
Statutory capital (1)	1,936,115		1,662,655		981,427

Risk-to-capital (2)	11.6:1		11.7:1		15.8:1

(1) Represents the total of the statutory surplus and contingency reserve.

(2) Excludes Re One as of December 31, 2021 as it had no risk in force remaining following the termination and commutation of the reinsurance agreement with

NMIC.

- Definition

Tabular disclosure of how the entity's reporting under GAAP as of the balance sheet date differs from the results based on prescribed and permitted accounting practices of the state or country of domicile in which a relevant statutory filing is made, or differences in results based on the National Association of Insurance Commissioners (NAIC) prescribed practices, or a combination thereof. Describes the accounting practices used and the related monetary effect on statutory surplus, net income, and risk-based capital. If an insurance enterprise's risk-based capital would have triggered a regulatory event had it not used a permitted practice, that fact is disclosed in the financial statements. Permitted statutory accounting practices include practices not prescribed but allowed by the domiciliary state insurance department regulatory authority.

+ References + Details

Quarterly Financial Data (Unaudited) (Tables)

12 Months Ended

Dec. 31, 2021

Quarterly Financial Information Disclosure [Abstract]

Schedule of quarterly financial information


	2021 Quarters								2021
	First		Second		Third		Fourth		Year
	(In Thousands, except per share data)

Net premiums earned	$	105,879	$	110,888	$	113,594	$	113,933	$	444,294
Net investment income	8,814		9,382		9,831		10,045		38,072
Net realized investment gains	—		12		3		714		729
Other revenues	501		483		613		380		1,977

Insurance claims and claim expenses (benefit)	4,962		4,640		3,204		(500)		12,305		(2)

Underwriting and operating expenses	34,065		34,725		34,669		38,843		142,303		(2)
Service expenses	591		481		787		650		2,509
Interest expense	7,915		7,922		7,930		8,029		31,796
Loss (gain) from change in fair value of warrant liability	205		(658)		—		(112)		(566)		(2)
Pre-tax income	67,456		73,655		77,451		78,162		296,725		(2)
Income tax expense	14,565		16,133		17,258		17,639		65,595
Net income	$	52,891	$	57,522	$	60,193	$	60,523	$	231,130	(2)

Basic earnings per share (1)	$	0.62	$	0.67	$	0.70	$	0.71	$	2.70
Diluted earnings per share (1)	$	0.61	$	0.65	$	0.69	$	0.69	$	2.65

Weighted average common shares outstanding - basic	85,317		85,647		85,721		85,757		85,620
Weighted average common shares outstanding - diluted	86,487		86,819		86,880		87,117		86,885

(1) Due to the use of weighted average shares outstanding when calculating EPS, the sum of quarterly per share data may not equal the per share data for the year.

(2) May not foot by summing up the quarterly results due to rounding.


	2020 Quarters								2020
	First		Second		Third		Fourth		Year
	(In Thousands, except per share data)

Net premiums earned	$	98,717	$	98,944	$	98,802	$	100,709	$	397,172
Net investment income	8,104		7,070		8,337		8,386		31,897
Net realized investment (losses) gains	(72)		711		(4)		295		930
Other revenues	900		1,223		648		513		3,284

Insurance claims and claim expenses	5,697		34,334		15,667		3,549		59,247
Underwriting and operating expenses	32,277		30,370		33,969		34,994		131,610
Service expenses	734		1,090		557		459		2,840
Interest expense	2,744		5,941		7,796		7,906		24,387
(Gain) loss from change in fair value of warrant liability	(5,959)		1,236		437		1,379		(2,907)
Pre-tax income	72,156		34,977		49,357		61,616		218,106
Income tax expense	13,885		8,129		11,178		13,348		46,540
Net income	$	58,271	$	26,848	$	38,179	$	48,268	$	171,566

Basic earnings per share (1)	$	0.85	$	0.36	$	0.45	$	0.57	$	2.20
Diluted earnings per share (1)	$	0.74	$	0.36	$	0.45	$	0.56	$	2.13

Weighted average common shares outstanding - basic	68,563		73,617		84,805		84,956		78,023
Weighted average common shares outstanding - diluted	70,401		74,174		85,599		86,250		79,263

(1) Due to the use of weighted average shares outstanding when calculating EPS, the sum of quarterly per share data may not equal the per share data for the year.

Organization and Basis of Presentation (Details) $ in Millions	12 Months Ended
	Dec. 31, 2021 USD ($) state
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of states in which the entity operates \| state	50
Severance restricted stock modification and other expenses related to CEO transition \| $	$ 3.8

Summary of Accounting Principles (Details) - USD ($)	12 Months Ended
Summary of Accounting Principles (Details) - USD ($)	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Finite-Lived Intangible Assets [Line Items]
Accrued interest receivable	$ 11,900,000
Amortization of deferred acquisition expense	22,800,000	$ 19,100,000	$ 8,400,000
Premium deficiency reserve expense	0	0	$ 0
Reinsurance recoverable	20,320,000	17,608,000
Impairments of goodwill	0
Impairment of indefinite-lived intangible assets	$ 0
Premium receivable, number of days to be written off	120 days
Premium receivable, write-off reserve	$ 2,300,000	$ 1,600,000
Software \| Minimum
Finite-Lived Intangible Assets [Line Items]
Estimated useful life		3 years
Software \| Maximum
Finite-Lived Intangible Assets [Line Items]
Estimated useful life		5 years
Equipment \| Minimum
Finite-Lived Intangible Assets [Line Items]
Estimated useful life	3 years
Equipment \| Maximum
Finite-Lived Intangible Assets [Line Items]
Estimated useful life	5 years
Geographic Concentration Risk \| Risk-in-Force \| CALIFORNIA
Finite-Lived Intangible Assets [Line Items]
Concentration risk	10.00%	11.00%	12.00%

Investments - Fair Values and Gross Unrealized Gains and Losses (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 2,078,773	$ 1,730,835
Gross Unrealized Gains	30,353	73,963
Gross Unrealized Losses	(23,195)	(512)
Fair Value	2,085,931	1,804,286
U.S. Treasury securities and obligations of U.S. government agencies
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	29,443	29,412
Gross Unrealized Gains	981	2,186
Gross Unrealized Losses	0	0
Fair Value	30,424	31,598
Municipal debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	553,793	407,323
Gross Unrealized Gains	5,689	14,027
Gross Unrealized Losses	(5,404)	(2)
Fair Value	554,078	421,348
Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,388,204	1,165,260
Gross Unrealized Gains	22,990	55,014
Gross Unrealized Losses	(17,364)	(483)
Fair Value	1,393,830	1,219,791
Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	96,324	128,471
Gross Unrealized Gains	684	2,736
Gross Unrealized Losses	(427)	(27)
Fair Value	96,581	131,180
Total bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,067,764	1,730,466
Gross Unrealized Gains	30,344	73,963
Gross Unrealized Losses	(23,195)	(512)
Fair Value	2,074,913	1,803,917
Short-term investments
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	11,009	369
Gross Unrealized Gains	9	0
Gross Unrealized Losses	0	0
Fair Value	$ 11,018	$ 369

Investments - Corporate Debt Securities by Industry Group (Details)	Dec. 31, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale [Line Items]
Corporate debt securities as component of total (percent)	100.00%	100.00%
Financial
Debt Securities, Available-for-sale [Line Items]
Corporate debt securities as component of total (percent)	38.00%	37.00%
Consumer
Debt Securities, Available-for-sale [Line Items]
Corporate debt securities as component of total (percent)	24.00%	23.00%
Communications
Debt Securities, Available-for-sale [Line Items]
Corporate debt securities as component of total (percent)	11.00%	10.00%
Utilities
Debt Securities, Available-for-sale [Line Items]
Corporate debt securities as component of total (percent)	10.00%	11.00%
Technology
Debt Securities, Available-for-sale [Line Items]
Corporate debt securities as component of total (percent)	9.00%	10.00%
Industrial
Debt Securities, Available-for-sale [Line Items]
Corporate debt securities as component of total (percent)	8.00%	9.00%

Investments - Narrative (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale [Line Items]
Unrealized loss position, accumulated loss	$ 23,195	$ 512
Unrealized loss position, 12 months or greater	6,453	8
U.S. Treasury securities and obligations of U.S. government agencies
Debt Securities, Available-for-sale [Line Items]
Cash and investments held with various state insurance departments	$ 5,600	$ 5,700

Investments - Scheduled Maturities (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Amortized Cost
Due in one year or less	$ 81,699	$ 57,429
Due after one through five years	630,625	507,444
Due after five through ten years	1,215,224	1,016,230
Due after ten years	54,901	21,261
Asset-backed securities	96,324	128,471
Amortized Cost	2,078,773	1,730,835
Fair Value
Due in one year or less	82,201	57,949
Due after one through five years	644,447	536,520
Due after five through ten years	1,207,997	1,056,098
Due after ten years	54,705	22,539
Asset-backed securities	96,581	131,180
Fair Value	$ 2,085,931	$ 1,804,286

Investments - Aging of Unrealized Losses (Details) $ in Thousands	Dec. 31, 2021 USD ($) security	Dec. 31, 2020 USD ($) security
Debt Securities, Available-for-sale [Line Items]
Number of securities, less than 12 months \| security	276	15
Fair value, less than 12 months	$ 1,025,912	$ 48,820
Unrealized losses, less than 12 months	$ (16,742)	$ (504)
Number of securities,12 months or greater \| security	23	2
Fair value, 12 months or greater	$ 156,118	$ 2,528
Unrealized losses, 12 months or greater	$ (6,453)	$ (8)
Number of securities, total \| security	299	17
Fair Value	$ 1,182,030	$ 51,348
Unrealized Losses	$ (23,195)	$ (512)
Municipal debt securities
Debt Securities, Available-for-sale [Line Items]
Number of securities, less than 12 months \| security	151	4
Fair value, less than 12 months	$ 314,823	$ 3,548
Unrealized losses, less than 12 months	$ (4,959)	$ (2)
Number of securities,12 months or greater \| security	2	0
Fair value, 12 months or greater	$ 8,138	$ 0
Unrealized losses, 12 months or greater	$ (445)	$ 0
Number of securities, total \| security	153	4
Fair Value	$ 322,961	$ 3,548
Unrealized Losses	$ (5,404)	$ (2)
Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Number of securities, less than 12 months \| security	114	9
Fair value, less than 12 months	$ 653,488	$ 40,081
Unrealized losses, less than 12 months	$ (11,426)	$ (483)
Number of securities,12 months or greater \| security	20	1
Fair value, 12 months or greater	$ 146,003	$ 33
Unrealized losses, 12 months or greater	$ (5,938)	$ 0
Number of securities, total \| security	134	10
Fair Value	$ 799,491	$ 40,114
Unrealized Losses	$ (17,364)	$ (483)
Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Number of securities, less than 12 months \| security	11	2
Fair value, less than 12 months	$ 57,601	$ 5,191
Unrealized losses, less than 12 months	$ (357)	$ (19)
Number of securities,12 months or greater \| security	1	1
Fair value, 12 months or greater	$ 1,977	$ 2,495
Unrealized losses, 12 months or greater	$ (70)	$ (8)
Number of securities, total \| security	12	3
Fair Value	$ 59,578	$ 7,686
Unrealized Losses	$ (427)	$ (27)

Investments - Net Investment Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Investments, Debt and Equity Securities [Abstract]
Investment income	$ 39,385	$ 33,140	$ 31,332
Investment expenses	(1,313)	(1,243)	(476)
Net investment income	$ 38,072	$ 31,897	$ 30,856

Investments - Net Realized Investments Gains (Losses) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Investments, Debt and Equity Securities [Abstract]
Gross realized investment gains	$ 729	$ 5,572	$ 561
Gross realized investment losses	0	(4,642)	(516)
Net realized investment gains	$ 729	$ 930	$ 45

Fair Value of Financial Instruments - Assets and Liabilities at Fair Value (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	$ 2,085,931	$ 1,804,286
U.S. Treasury securities and obligations of U.S. government agencies
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	30,424	31,598
Municipal debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	554,078	421,348
Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	1,393,830	1,219,791
Asset-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	96,581	131,180
Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash, cash equivalents and short-term investments	87,664	127,306
Total assets	2,162,577	1,931,223
Warrant liability	2,363	4,409
Total liabilities	2,363	4,409
Recurring \| U.S. Treasury securities and obligations of U.S. government agencies
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	30,424	31,598
Recurring \| Municipal debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	554,078	421,348
Recurring \| Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	1,393,830	1,219,791
Recurring \| Asset-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	96,581	131,180
Recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash, cash equivalents and short-term investments	87,664	127,306
Total assets	118,088	158,904
Warrant liability	0	0
Total liabilities	0	0
Recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| U.S. Treasury securities and obligations of U.S. government agencies
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	30,424	31,598
Recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| Municipal debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| Asset-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Recurring \| Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash, cash equivalents and short-term investments	0	0
Total assets	2,044,489	1,772,319
Warrant liability	0	0
Total liabilities	0	0
Recurring \| Significant Other Observable Inputs (Level 2) \| U.S. Treasury securities and obligations of U.S. government agencies
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Recurring \| Significant Other Observable Inputs (Level 2) \| Municipal debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	554,078	421,348
Recurring \| Significant Other Observable Inputs (Level 2) \| Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	1,393,830	1,219,791
Recurring \| Significant Other Observable Inputs (Level 2) \| Asset-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	96,581	131,180
Recurring \| Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash, cash equivalents and short-term investments	0	0
Total assets	0	0
Warrant liability	2,363	4,409
Total liabilities	2,363	4,409
Recurring \| Significant Unobservable Inputs (Level 3) \| U.S. Treasury securities and obligations of U.S. government agencies
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Recurring \| Significant Unobservable Inputs (Level 3) \| Municipal debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Recurring \| Significant Unobservable Inputs (Level 3) \| Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Recurring \| Significant Unobservable Inputs (Level 3) \| Asset-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	$ 0	$ 0

Fair Value of Financial Instruments - Rollfoward of Level 3 Liabilities (Details) - Significant Unobservable Inputs (Level 3) - Warrant liability - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	$ 4,409	$ 7,641	$ 7,296
Change in fair value of warrant liability included in earnings	(566)	(2,907)	8,657
Issuance of common stock on warrant exercise	(1,480)	(325)	(8,312)
Ending balance	$ 2,363	$ 4,409	$ 7,641

Fair Value of Financial Instruments - Valuation Assumptions for Warrant Liabilities (Details) - Significant Unobservable Inputs (Level 3) - Valuation Technique, Option Pricing Model	Dec. 31, 2021 $ / shares	Dec. 31, 2020 $ / shares	Dec. 31, 2019 $ / shares
Common stock price
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrant liability, measurement input	21.85	22.65	33.18
Risk free interest rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrant liability, measurement input	0.0007	0.0011	0.0159
Expected life
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrant liability, expected life (in years)	3 months 21 days	1 year 3 months 21 days	2 years 3 months 21 days
Expected volatility
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrant liability, measurement input	0.263	0.837	0.414
Dividend yield
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrant liability, measurement input	0	0	0

Fair Value of Financial Instruments - Narrative (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Jun. 19, 2020	Jan. 19, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt	$ 394,623	$ 393,301
Secured Debt
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Senior notes			$ 400,000
Deferred debt issuance costs	5,400	6,700	$ 7,400
Debt	394,600	393,300
Secured Debt \| 2018 Term loan
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt instrument face amount				$ 150,000
Secured Debt \| Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of term loan	$ 454,600	$ 447,100

- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References + Details

Debt (Details) - USD ($)				12 Months Ended
Debt (Details) - USD ($)	Nov. 29, 2021	Jun. 19, 2020	Mar. 20, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Nov. 28, 2021	Mar. 19, 2020
Debt Instrument [Line Items]
Proceeds from senior secured notes				$ 0	$ 400,000,000	$ 0
2018 Term loan
Debt Instrument [Line Items]
Loss on extinguishment of debt					2,600,000
Interest payable				2,500,000	2,500,000
2020 Revolving credit facility
Debt Instrument [Line Items]
Deferred debt issuance costs								$ 600,000
Revolving credit facility
Debt Instrument [Line Items]
Commitment fees in interest expense				400,000
Revolving credit facility \| 2020 Revolving credit facility
Debt Instrument [Line Items]
Credit facility borrowing capacity	$ 250,000,000			250,000,000			$ 110,000,000
Borrowings outstanding				$ 0	0
Commitment fee (in percent)				0.35%
Remaining deferred issuance costs, net of accumulated amortization				$ 1,600,000
Revolving credit facility \| 2020 Revolving credit facility \| Minimum
Debt Instrument [Line Items]
Commitment fee (in percent)			0.175%
Revolving credit facility \| 2020 Revolving credit facility \| Maximum
Debt Instrument [Line Items]
Commitment fee (in percent)			0.525%
Revolving credit facility \| 2021 Revolving credit facility
Debt Instrument [Line Items]
Debt Issuance costs			$ 1,100,000
Maximum debt-to-total capitalization (in percent)				35.00%
Revolving credit facility \| 2021 Revolving credit facility \| Base rate
Debt Instrument [Line Items]
Variable rate floor (in percent)	100.00%
Revolving credit facility \| 2021 Revolving credit facility \| Minimum
Debt Instrument [Line Items]
Commitment fee (in percent)			0.175%
Revolving credit facility \| 2021 Revolving credit facility \| Minimum \| Base rate
Debt Instrument [Line Items]
Basis spread on variable rate (in percent)			0.375%
Revolving credit facility \| 2021 Revolving credit facility \| Minimum \| Eurodollar
Debt Instrument [Line Items]
Basis spread on variable rate (in percent)			1.375%
Revolving credit facility \| 2021 Revolving credit facility \| Maximum
Debt Instrument [Line Items]
Commitment fee (in percent)			0.525%
Revolving credit facility \| 2021 Revolving credit facility \| Maximum \| Base rate
Debt Instrument [Line Items]
Basis spread on variable rate (in percent)			1.875%
Revolving credit facility \| 2021 Revolving credit facility \| Maximum \| Eurodollar
Debt Instrument [Line Items]
Basis spread on variable rate (in percent)			2.875%
General corporate purposes
Debt Instrument [Line Items]
Proceeds from senior secured notes		$ 244,400,000
Secured Debt
Debt Instrument [Line Items]
Senior notes		$ 400,000,000
Stated interest rate (in percent)				7.375%
Applicable premium		1.00%
Percent of aggregate balance redeemable with equity offerings		40.00%
Deferred debt issuance costs		$ 7,400,000		$ 5,400,000	$ 6,700,000
Secured Debt \| Prior to March 1, 2025
Debt Instrument [Line Items]
Redemption price (in percent)		100.00%
Secured Debt \| After March 1, 2025
Debt Instrument [Line Items]
Redemption price (in percent)		100.00%
Secured Debt \| Prior to June 1, 2022
Debt Instrument [Line Items]
Redemption price (in percent)		107.375%

Reinsurance - Effect of Reinsurance Agreements on Premiums Written and Earned (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Net premiums written
Direct									$ 557,050	$ 455,172	$ 376,052
Ceded									(88,539)	(66,528)	(43,400)
Net premiums written									468,511	388,644	332,652
Net premiums earned
Direct										472,998	398,303
Ceded									(92,336)	(75,826)	(53,288)
Net premiums earned	$ 113,933	$ 113,594	$ 110,888	$ 105,879	$ 100,709	$ 98,802	$ 98,944	$ 98,717	$ 444,294	$ 397,172	$ 345,015

Reinsurance - Narrative (Details) - USD ($) $ in Thousands			12 Months Ended
Reinsurance - Narrative (Details) - USD ($) $ in Thousands	Apr. 01, 2019	Mar. 31, 2019	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Ceded Credit Risk [Line Items]
Restricted cash			$ 3,165	$ 5,555
Reinsurance recoverable on unpaid claims			$ 20,320	17,608	$ 4,939	$ 3,001
ILN Transactions
Ceded Credit Risk [Line Items]
Reinsurance coverage, term of underlying mortgage amortization (in years)			10 years
Optional termination right, percent of reinsurance coverage threshold			10.00%
2018 QSR Transaction
Ceded Credit Risk [Line Items]
Reinsurance recoverable on unpaid claims			$ 15,700
2020 QSR Transaction
Ceded Credit Risk [Line Items]
Reinsurance recoverable on unpaid claims			15,700
2021 QSR Transaction
Ceded Credit Risk [Line Items]
Reinsurance recoverable on unpaid claims			$ 15,700
Maximum
Ceded Credit Risk [Line Items]
Reinsurance coverage, term of underlying mortgage amortization (in years)			12 years 6 months
Third-Party Reinsurers \| 2017 ILN Transaction
Ceded Credit Risk [Line Items]
Risk premiums paid			$ 41,300	$ 22,800	$ 14,600
Third-Party Reinsurers \| QSR Transactions
Ceded Credit Risk [Line Items]
Ceding commissions under QSR Transaction			20.00%
Third-Party Reinsurers \| Eligible policies, pool one
Ceded Credit Risk [Line Items]
Percent of premiums ceded under QSR Transaction	20.50%	25.00%
Third-Party Reinsurers \| Fannie Mae
Ceded Credit Risk [Line Items]
Percent of premiums ceded under QSR Transaction			100.00%
Third-Party Reinsurers \| Risk Written Policies in 2018
Ceded Credit Risk [Line Items]
Premiums of premiums earned under QSR Transaction			25.00%
Third-Party Reinsurers \| Risk Written Policies in 2019
Ceded Credit Risk [Line Items]
Percent of premiums ceded under QSR Transaction			20.00%
Third-Party Reinsurers \| Risk written policies in 2020
Ceded Credit Risk [Line Items]
Premiums of premiums earned under QSR Transaction			21.00%
Third-Party Reinsurers \| Risk written policies in 2021
Ceded Credit Risk [Line Items]
Premiums of premiums earned under QSR Transaction			22.50%
Third-Party Reinsurers \| Risk written policies in 2022
Ceded Credit Risk [Line Items]
Premiums of premiums earned under QSR Transaction			20.00%
Third-Party Reinsurers \| Risk written policies in 2023
Ceded Credit Risk [Line Items]
Premiums of premiums earned under QSR Transaction			20.00%
Third-Party Reinsurers \| 2016 QSR Transaction
Ceded Credit Risk [Line Items]
Previously Ceded Primary Risk-In-Force Recaptured	$ 500,000
Threshold for loss ratio on loans to qualify for profit commission			60.00%
Reinsurance recoverable on unpaid claims			$ 4,600
Third-Party Reinsurers \| 2018 QSR Transaction
Ceded Credit Risk [Line Items]
Threshold for loss ratio on loans to qualify for profit commission			61.00%
Third-Party Reinsurers \| 2020 QSR Transaction
Ceded Credit Risk [Line Items]
Threshold for loss ratio on loans to qualify for profit commission			50.00%
Third-Party Reinsurers \| 2021 QSR Transaction
Ceded Credit Risk [Line Items]
Threshold for loss ratio on loans to qualify for profit commission			57.50%
Third-Party Reinsurers \| 2023 QSR Transaction
Ceded Credit Risk [Line Items]
Threshold for loss ratio on loans to qualify for profit commission			62.00%
Third-Party Reinsurers \| 2022 QSR Transaction
Ceded Credit Risk [Line Items]
Threshold for loss ratio on loans to qualify for profit commission			62.00%
Third-Party Reinsurers \| Maximum \| 2017 ILN Transaction
Ceded Credit Risk [Line Items]
Anticipated payment related to annual operating expenses			$ 250
Third-Party Reinsurers \| Maximum \| 2018 ILN Transaction
Ceded Credit Risk [Line Items]
Anticipated payment related to annual operating expenses			$ 300

Reinsurance - ILN Transactions (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Oct. 26, 2021	Apr. 27, 2021	Oct. 29, 2020	Jul. 30, 2020	Jul. 30, 2019	Jul. 25, 2018	May 02, 2017
2017 ILN Transaction
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Initial Reinsurance Coverage								$ 211,320
Current Reinsurance Coverage	$ 27,425
Initial First Layer Retained Loss								$ 126,793
Current First Layer Retained Loss	121,163
2018 ILN Transaction
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Initial Reinsurance Coverage							$ 264,545
Current Reinsurance Coverage	158,489
Initial First Layer Retained Loss							$ 125,312
Current First Layer Retained Loss	122,569
2019 ILN Transaction
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Initial Reinsurance Coverage						$ 326,905
Current Reinsurance Coverage	231,877
Initial First Layer Retained Loss						$ 123,424
Current First Layer Retained Loss	122,548
2020-1 ILN Transaction
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Initial Reinsurance Coverage					$ 322,076
Current Reinsurance Coverage	49,879
Initial First Layer Retained Loss					$ 169,514
Current First Layer Retained Loss	169,488
2020-2 ILN Transaction
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Initial Reinsurance Coverage				$ 242,351
Current Reinsurance Coverage	155,129
Initial First Layer Retained Loss				$ 121,777
Current First Layer Retained Loss	$ 121,177
Percentage of population with production prior to April 1, 2020 (less than)	1.00%
2021-1 ILN Transaction
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Initial Reinsurance Coverage			$ 367,238
Current Reinsurance Coverage	$ 367,238
Initial First Layer Retained Loss			$ 163,708
Current First Layer Retained Loss	$ 163,708
Percentage of population with production prior to April 1, 2020 (less than)	1.00%
2021-2 ILN Transaction
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Initial Reinsurance Coverage		$ 363,596
Current Reinsurance Coverage	$ 363,596
Initial First Layer Retained Loss		$ 146,229
Current First Layer Retained Loss	$ 146,229
Percentage of population with production prior to April 1, 2020 (less than)	2.00%

Reinsurance - Amounts Ceded Related to QSR Transactions (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Ceded Credit Risk [Line Items]
Ceded premiums earned	$ (92,336)	$ (75,826)	$ (53,288)
Third-Party Reinsurers
Ceded Credit Risk [Line Items]
Ceded risk-in-force	8,194,604	5,543,969	5,137,249
Ceded premiums earned	(110,140)	(94,899)	(89,211)
Ceded claims and claim expenses	3,233	14,002	3,465
Ceding commission earned	23,473	18,526	17,652
Profit commission	$ 59,104	$ 41,902	$ 50,513

Reserves for Insurance Claims and Claim Expenses - Narrative (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2021 USD ($) loan claim	Dec. 31, 2020 USD ($) loan policy	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Liability for Claims and Claims Adjustment Expense [Line Items]
Primary loans in default \| loan	6,227	12,209
Reserve for insurance claims and claim expenses	$ 103,551	$ 90,567	$ 23,752	$ 12,811
Number of claims paid \| claim	82
Claims paid, including amounts covered by insurance	$ 2,600
Total policies in-force	512,316	399,429
Default rate (in percent)	1.22%	3.06%
Reserve for prior year insurance claims and claims expense	$ 74,400
Fannie Mae
Liability for Claims and Claims Adjustment Expense [Line Items]
Number of loans in pool past due 60 days or more \| loan	96
Risk-in-Force of loans in pool past due 60 days or more	$ 7,300
Loan-to-value ratio (less than)	0.80
Claims applied to pool deductible	$ 1,000
Deductible on policy	$ 9,400
QSR Transactions
Liability for Claims and Claims Adjustment Expense [Line Items]
Number of covered claims included in number of claims paid \| claim	79
Claims paid QSR transaction	$ 500
2016 QSR Transaction \| Fannie Mae
Liability for Claims and Claims Adjustment Expense [Line Items]
Percent of pool RIF reinsured	100.00%

Reserves for Insurance Claims and Claim Expenses - Reconciliation of Reserve Balances for Insurance Claims and Claim Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward]
Beginning balance	$ 90,567	$ 23,752	$ 12,811
Less reinsurance recoverables	(17,608)	(4,939)	(3,001)
Beginning balance, net of reinsurance recoverables	72,959	18,813	9,810
Claims and claim expenses incurred:
Current year	23,433	66,943	14,737
Prior years	(11,128)	(7,696)	(2,230)
Total claims and claim expenses incurred	12,305	59,247	12,507
Claims and claim expenses paid:
Current year	16	586	204
Prior years	2,017	4,515	3,849
Reinsurance terminations	0	0	(549)
Total claims and claim expenses paid	2,033	5,101	3,504
Reserve at end of period, net of reinsurance recoverables	83,231	72,959	18,813
Add reinsurance recoverables	20,320	17,608	4,939
Ending balance	103,551	90,567	23,752
Current year case reserves	18,100	60,800	13,200
Current year IBNR	4,700	5,000	1,300
Prior year case reserves	(6,300)	(6,200)	(1,500)
Prior year, IBNR	$ (5,000)	$ (1,300)	$ (700)

Reserves for Insurance Claims and Claim Expenses - Claim Development by Accident Year and Reconciliation of Reserve for Insurance Claims and Claims Expense (Details)	Dec. 31, 2021 USD ($) claim	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Claims Development [Line Items]
Cumulative Paid Claims and Claims Adjustment Expenses, net of Reinsurance	$ 14,743,000
2021
Claims Development [Line Items]
Total of IBNR	$ 362,000
NODs \| claim	3,393
Cumulative Paid Claims and Claims Adjustment Expenses, net of Reinsurance	$ 16,000
Financial Guarantee Insurance Product Line
Claims Development [Line Items]
Cumulative Incurred Claims and Allocated Claims Adjustment Expenses, net of Reinsurance	95,859,000
Total of IBNR	$ 4,731,000
NODs \| claim	6,227
Cumulative Paid Claims and Claims Adjustment Expenses, net of Reinsurance	$ 14,743,000
Financial Guarantee Insurance Product Line \| 2013
Claims Development [Line Items]
Cumulative Incurred Claims and Allocated Claims Adjustment Expenses, net of Reinsurance	0	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0
Total of IBNR	$ 0
NODs \| claim	0
Cumulative Paid Claims and Claims Adjustment Expenses, net of Reinsurance	$ 0	0	0	0	0	0	0	0	$ 0
Financial Guarantee Insurance Product Line \| 2014
Claims Development [Line Items]
Cumulative Incurred Claims and Allocated Claims Adjustment Expenses, net of Reinsurance	4,000	4,000	4,000	4,000	4,000	4,000	34,000	83,000
Total of IBNR	$ 0
NODs \| claim	0
Cumulative Paid Claims and Claims Adjustment Expenses, net of Reinsurance	$ 4,000	4,000	4,000	4,000	4,000	4,000	4,000	$ 0
Financial Guarantee Insurance Product Line \| 2015
Claims Development [Line Items]
Cumulative Incurred Claims and Allocated Claims Adjustment Expenses, net of Reinsurance	894,000	894,000	894,000	764,000	743,000	664,000	699,000
Total of IBNR	$ 0
NODs \| claim	0
Cumulative Paid Claims and Claims Adjustment Expenses, net of Reinsurance	$ 894,000	894,000	804,000	720,000	684,000	246,000	$ 50,000
Financial Guarantee Insurance Product Line \| 2016
Claims Development [Line Items]
Cumulative Incurred Claims and Allocated Claims Adjustment Expenses, net of Reinsurance	1,930,000	1,936,000	1,934,000	1,790,000	1,568,000	2,394,000
Total of IBNR	$ 4,000
NODs \| claim	3
Cumulative Paid Claims and Claims Adjustment Expenses, net of Reinsurance	$ 1,877,000	1,827,000	1,826,000	1,596,000	890,000	$ 171,000
Financial Guarantee Insurance Product Line \| 2017
Claims Development [Line Items]
Cumulative Incurred Claims and Allocated Claims Adjustment Expenses, net of Reinsurance	3,716,000	3,807,000	3,570,000	3,475,000	6,028,000
Total of IBNR	$ 5,000
NODs \| claim	9
Cumulative Paid Claims and Claims Adjustment Expenses, net of Reinsurance	$ 3,640,000	3,494,000	2,925,000	1,655,000	27,000
Financial Guarantee Insurance Product Line \| 2018
Claims Development [Line Items]
Cumulative Incurred Claims and Allocated Claims Adjustment Expenses, net of Reinsurance	4,533,000	4,709,000	5,271,000	7,779,000
Total of IBNR	$ 56,000
NODs \| claim	47
Cumulative Paid Claims and Claims Adjustment Expenses, net of Reinsurance	$ 3,780,000	3,537,000	1,981,000	$ 130,000
Financial Guarantee Insurance Product Line \| 2019
Claims Development [Line Items]
Cumulative Incurred Claims and Allocated Claims Adjustment Expenses, net of Reinsurance	5,781,000	7,229,000	14,391,000
Total of IBNR	$ 192,000
NODs \| claim	228
Cumulative Paid Claims and Claims Adjustment Expenses, net of Reinsurance	$ 3,212,000	2,368,000	$ 69,000
Financial Guarantee Insurance Product Line \| 2020
Claims Development [Line Items]
Cumulative Incurred Claims and Allocated Claims Adjustment Expenses, net of Reinsurance	56,154,000	65,769,000
Total of IBNR	$ 4,112,000
NODs \| claim	2,547
Cumulative Paid Claims and Claims Adjustment Expenses, net of Reinsurance	$ 1,320,000	$ 586,000
Financial Guarantee Insurance Product Line \| 2021
Claims Development [Line Items]
Cumulative Incurred Claims and Allocated Claims Adjustment Expenses, net of Reinsurance	$ 22,847,000

Reserves for Insurance Claims and Claim Expenses - Reconciliation of Disclosure of Incurred and Paid Claims Development to the Liability for Unpaid Claims and Claims Adjustment Expenses (Details) - USD ($)	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items]
Cumulative Paid Claims and Claims Adjustment Expenses, net of Reinsurance	$ 14,743,000
Reinsurance recoverable on unpaid claims	20,320,000	$ 17,608,000	$ 4,939,000	$ 3,001,000
Reserve for insurance claims and claim expenses	103,551,000	$ 90,567,000	$ 23,752,000	$ 12,811,000
Financial Guarantee Insurance Product Line
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items]
Cumulative Incurred Claims and Allocated Claims Adjustment Expenses, net of Reinsurance	95,859,000
Cumulative Paid Claims and Claims Adjustment Expenses, net of Reinsurance	14,743,000
Liabilities for unpaid claims and allocated claims adjustment expenses, net of reinsurance	81,116,000
Reinsurance recoverable on unpaid claims	20,320,000
Unallocated claims adjustment expenses	2,115,000
Reserve for insurance claims and claim expenses	$ 103,551,000

Reserves for Insurance Claims and Claim Expenses - Average Annual Percentage Payout of Incurred Claims by Age, Net of Reinsurance (Details) - Financial Guarantee Insurance Product Line	Dec. 31, 2021
Average annual percentage payout of incurred claims and allocated claims adjustment expenses by age, net of reinsurance
Year 1	2.00%
Year 2	32.00%
Year 3	82.00%
Year 4	93.00%
Year 5	96.00%
Year 6	99.00%
Year 7	100.00%
Year 8	100.00%

Earnings per Share (Details) - USD ($) $ / shares in Units, shares in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Basic EPS
Net income	$ 60,523,000	$ 60,193,000	$ 57,522,000	$ 52,891,000	$ 48,268,000	$ 38,179,000	$ 26,848,000	$ 58,271,000	$ 231,130,000	$ 171,566,000	$ 171,957,000
Basic weighted average shares outstanding (in shares)	85,757	85,721	85,647	85,317	84,956	84,805	73,617	68,563	85,620	78,023	67,573
Basic earnings per share (in dollars per share)	$ 0.71	$ 0.70	$ 0.67	$ 0.62	$ 0.57	$ 0.45	$ 0.36	$ 0.85	$ 2.70	$ 2.20	$ 2.54
Diluted EPS
Net income	$ 60,523,000	$ 60,193,000	$ 57,522,000	$ 52,891,000	$ 48,268,000	$ 38,179,000	$ 26,848,000	$ 58,271,000	$ 231,130,000	$ 171,566,000	$ 171,957,000
Gain from change in fair value of warrant liability									(566,000)	(2,907,000)	0
Diluted net income									$ 230,564,000	$ 168,659,000	$ 171,957,000
Basic weighted average shares outstanding (in shares)	85,757	85,721	85,647	85,317	84,956	84,805	73,617	68,563	85,620	78,023	67,573
Dilutive effect of issuable shares (in shares)									1,265	1,240	2,148
Diluted weighted average shares outstanding (in shares)	87,117	86,880	86,819	86,487	86,250	85,599	74,174	70,401	86,885	79,263	69,721
Diluted earnings per share (in dollars per share)	$ 0.69	$ 0.69	$ 0.65	$ 0.61	$ 0.56	$ 0.45	$ 0.36	$ 0.74	$ 2.65	$ 2.13	$ 2.47
Antidilutive securities excluded from EPS calculation (in shares)									3	58	565

Warrants (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Apr. 30, 2012
Debt Disclosure [Abstract]
Warrants issued (in shares)				992,000
Class of warrant or right, outstanding (in shares)	199,000
Right to purchase, number of shares per warrant (in shares)				1
Exercise price of warrants (in dollars per warrant)				$ 10.00
Warrant liability, at fair value	$ 2,363	$ 4,409		$ 5,100
Warrants exercised (in shares)	113,000	18,000
Stock issued upon exercise of warrants (in shares)	86,000	11,000
Fair value of warrant liability reclassified to additional paid in capital upon exercise	$ 1,500	$ 300
Change in fair value of warrant liability in current period	$ 100	$ 100	$ 4,100

Share-Based Compensation - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands			12 Months Ended
	May 11, 2017	Apr. 16, 2012	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	May 08, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense			$ 16,678	$ 11,115	$ 13,031
Income tax benefit related to share-based compensation			$ 3,500	$ 2,300	$ 2,700
Number of options vested (in shares)			1,300,000
Options exercised (in shares)			122,000	435,000	1,117,000
Aggregate intrinsic value of options exercised			$ 1,500
Weighted average exercise price for options vested (in dollars per share)			$ 13.51
Weighted average remaining contractual term			3 years 11 months 12 days
Options vested aggregate value			$ 11,100
Unrecognized compensation cost related to non-vested stock options			$ 14
Unrecognized compensation cost, period for recognition			1 month 13 days
Options granted (in shares)			0	0	163,000
Employer matching contribution, percent of match (up to)			100.00%
Employer matching contribution, percent of employees' gross pay (up to)			5.00%
Contribution amount			$ 2,000	$ 2,200	$ 2,500
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units outstanding (in shares)			1,075,000	1,062,000	1,202,000	1,753,000
Fair value of shares vested			$ 10,700
Weighted average remaining contractual life of RSUs outstanding			1 year 2 months 26 days	1 year 3 months
Unrecognized compensation cost related to RSUs			$ 8,800	$ 8,800
Restricted Stock Units (RSUs) \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based awards vesting period (in years)			1 year
Restricted Stock Units (RSUs) \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based awards vesting period (in years)			5 years
RSUs Subject to Service Conditions
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units outstanding (in shares)			900,000
RSUs Subject to Service and Performance Conditions
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units outstanding (in shares)			200,000
2012 Stock Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized to be reserved for issuance (in shares)		5,500,000
2012 Stock Incentive Plan \| Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized to be reserved for issuance (in shares)		3,850,000
Expiration period (not more than)		10 years	10 years
Award requisite service period		3 years
2012 Stock Incentive Plan \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized to be reserved for issuance (in shares)		1,650,000
2014 Omnibus Incentive Plan \| Common Class A
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized to be reserved for issuance (in shares)	6,000,000						4,000,000
Additional shares authorized (in shares)	2,000,000

Share-Based Compensation - Stock Option Activity (Details) - $ / shares	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Shares
Options beginning balance (in shares)	1,493,000	1,928,000	2,882,000
Options granted (in shares)	0	0	163,000
Options exercised (in shares)	(122,000)	(435,000)	(1,117,000)
Options forfeited (in shares)	0	0	0
Options expired (in shares)	0	0	0
Options ending balance (in shares)	1,371,000	1,493,000	1,928,000
Weighted Average Grant Date Fair Value per Share
Options beginning balance (in dollars per share)	$ 5.02	$ 4.84	$ 4.24
Options granted (in dollars per share)	0	0	8.85
Options exercised (in dollars per share)	(4.43)	4.21	3.88
Options forfeited (in dollars per share)	0	0	0
Options expired (in dollars per share)	0	0	0
Options ending balance (in dollars per share)	5.07	5.02	4.84
Weighted Average Exercise Price
Options beginning balance (in dollars per share)	13.59	13.04	11.42
Options granted (in dollars per share)	0	0	22.19
Options exercised (in dollars per share)	11.42	11.17	10.19
Options forfeited (in dollars per share)	0	0	0
Options expired (in dollars per share)	0	0	0
Options beginning balance (in dollars per share)	$ 13.78	$ 13.59	$ 13.04

Share-Based Compensation - Stock Option Valuation Assumptions (Details) - Stock Options	12 Months Ended
	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected life (in years)	6 years
Risk free interest rate (percent)	2.57%
Dividend yield (percent)	0.00%
Expected stock price volatility (percent)	36.80%

Share-Based Compensation - Restricted Stock Units Activity (Details) - Restricted Stock Units (RSUs) - $ / shares shares in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Shares
Non-vested restricted stock units, beginning balance (in shares)	1,062	1,202	1,753
Restricted stock units granted (in shares)	589	646	470
Restricted stock units vested (in shares)	(536)	(664)	(970)
Restricted stock units forfeited (in shares)	(40)	(122)	(51)
Non-vested restricted stock units, ending balance (in shares)	1,075	1,062	1,202
Weighted Average Grant Date Fair Value per Share
Non-vested restricted stock units, beginning balance (in dollars per share)	$ 21.61	$ 18.67	$ 12.06
Restricted stock units granted (in dollars per share)	23.73	22.67	24.42
Restricted stock units vested (in dollars per share)	19.98	17.68	9.71
Restricted stock units forfeited (in dollars per share)	21.58	19.55	15.06
Non-vested restricted stock units, ending balance (in dollars per share)	$ 23.59	$ 21.61	$ 18.67

Income Taxes - Components of Income Tax Expense (Benefit) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Current									$ 85	$ 34	$ (386)
Deferred									65,510	46,506	45,082
Total income tax expense	$ 17,639	$ 17,258	$ 16,133	$ 14,565	$ 13,348	$ 11,178	$ 8,129	$ 13,885	$ 65,595	$ 46,540	$ 44,696

- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References + Details

Income Taxes - Narrative (Details) - USD ($)	3 Months Ended								12 Months Ended
Income Taxes - Narrative (Details) - USD ($)	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Tax Contingency [Line Items]
Income tax expense	$ 17,639,000	$ 17,258,000	$ 16,133,000	$ 14,565,000	$ 13,348,000	$ 11,178,000	$ 8,129,000	$ 13,885,000	$ 65,595,000	$ 46,540,000	$ 44,696,000
Purchases of T&L Bonds									42,900,000	38,800,000	7,600,000
Tax and loss bonds	89,200,000				46,400,000				89,200,000	46,400,000
Loss carry forwards subject to expiration	7,300,000								7,300,000
Valuation allowance	8,582,000				7,610,000				8,582,000	7,610,000
Unrecognized tax benefits reserve	0				$ 0				0	0
Annual Limitation Through Year Two
Income Tax Contingency [Line Items]
Loss carry forwards subject to expiration	800,000								800,000
Annual Limitations After Year Two
Income Tax Contingency [Line Items]
Loss carry forwards subject to expiration	300,000								300,000
Domestic Tax Authority \| IRS
Income Tax Contingency [Line Items]
Income tax expense									0	$ 0	$ 0
Operating loss carryforwards	1,800,000								1,800,000
State and Local Jurisdiction
Income Tax Contingency [Line Items]
Operating loss carryforwards	$ 132,400,000								$ 132,400,000

Income Taxes - Effective Income Tax Rate Reconciliation (Details)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Federal statutory income tax rate	21.00%	21.00%	21.00%
State provision	0.50%	0.50%	0.50%
Share-based and other compensation	0.60%	0.10%	(1.70%)
Warrant gain/loss	0.00%	(0.30%)	0.90%
Other	0.00%	0.00%	(0.10%)
Effective income tax rate	22.10%	21.30%	20.60%

Income Taxes - Deferred Tax Asset and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Deferred tax asset
Net operating loss carry forwards	$ 8,759	$ 7,938
Share-based compensation	6,090	5,067
Unearned premium reserve	5,878	4,844
Accrued expenses	2,852	3,198
Other	1,067	1,592
Total gross deferred tax asset	24,646	22,639
Less: valuation allowance	(8,582)	(7,610)
Total deferred tax asset	16,064	15,029
Deferred tax liability
Contingency reserve	(157,919)	(91,429)
Deferred acquisition costs	(12,797)	(13,381)
Capitalized software	(7,286)	(5,569)
Unrealized gain on investments	(1,503)	(15,432)
Other	(734)	(1,804)
Total deferred tax liability	(180,239)	(127,615)
Net deferred income tax (liability)	$ (164,175)	$ (112,586)

Software and Equipment - Net Balances (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Property plant and equipment	$ 85,537	$ 72,203
Accumulated amortization and depreciation	(53,490)	(42,538)
Software and equipment, net	32,047	29,665
Software
Property, Plant and Equipment [Line Items]
Property plant and equipment	72,481	59,677
Equipment
Property, Plant and Equipment [Line Items]
Property plant and equipment	9,654	9,123
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property plant and equipment	$ 3,402	$ 3,402

Software and Equipment - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Abstract]
Capitalized costs related to software, equipment, and leaseholds	$ 13.6	$ 14.5	$ 10.6
Depreciation and amortization	$ 11.2	$ 9.9	$ 9.3

Intangible Assets and Goodwill (Details) - USD ($)	12 Months Ended
Intangible Assets and Goodwill (Details) - USD ($)	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Indefinite-lived Intangible Assets [Line Items]
Goodwill	$ 3,244,000	$ 3,244,000
Total intangible assets and goodwill	3,634,000	3,634,000
Impairment loss related to intangible assets or goodwill	0	0	$ 0
State licenses
Indefinite-lived Intangible Assets [Line Items]
Intangible assets	260,000	260,000
GSE applications
Indefinite-lived Intangible Assets [Line Items]
Intangible assets	$ 130,000	$ 130,000

Commitments and Contingencies - Narrative (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2021 USD ($) lease_agreement	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Mar. 31, 2022 USD ($)	Jan. 01, 2022 USD ($)
Lessee, Lease, Description [Line Items]
Approved insurers, required assets (equal or greater than)	$ 400,000
Approved insurers, risked-based required assets, primary insurance floor	5.60%
Number of operating leases related to corporate headquarters and data center facility \| lease_agreement	2
Right-of-use lease assets	$ 2,600	$ 4,600
Operating lease liabilities	2,901	5,300
Right-of-use assets obtained in exchange for new operating lease liabilities			$ 8,100
Cash paid for amounts included in the measurement of operating lease liabilities	2,600	2,500	2,500
Operating lease expense	$ 2,300	$ 2,300	$ 2,200
Operating Lease, Liability, Statement of Financial Position [Extensible List]	Other liabilities	Other liabilities
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	Other assets	Other assets
Corporate Headquarters
Lessee, Lease, Description [Line Items]
Operating lease option to renew, term	5 years
Minimum
Lessee, Lease, Description [Line Items]
Operating lease terms	3 years
Maximum
Lessee, Lease, Description [Line Items]
Operating lease terms	7 years
Subsequent Event
Lessee, Lease, Description [Line Items]
Future lease payments modified lease					$ 15,900
Forecast
Lessee, Lease, Description [Line Items]
Operating lease liabilities				$ 9,000

Commitments and Contingencies - Right-of-Use Asset and Lease Liability Assumptions (Details)	Dec. 31, 2021
Commitments and Contingencies Disclosure [Abstract]
Weighted-average remaining lease term (in years)	1 year 2 months 12 days
Weighted-average discount rate	6.21%

Commitments and Contingencies - Future Payment Due Under Operating Leases (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Commitments and Contingencies Disclosure [Abstract]
2022	$ 2,574
2023	462
Total undiscounted lease payments	3,036
Less effects of discounting	(135)
Present value of lease payments	$ 2,901	$ 5,300

Common Stock - Narrative (Details) - USD ($) $ in Millions	Jun. 08, 2020	Dec. 31, 2021	Dec. 31, 2020
Class of Stock [Line Items]
Common stock, outstanding (in shares)		85,792,849	85,163,039
Public Stock Offering \| Common Stock - Class A
Class of Stock [Line Items]
Shares issued from sale of stock (in shares)	15,900,000
Proceeds from sale of stock	$ 219.7

Regulatory Information - Schedule of Combined Statutory Net Loss, Statutory Surplus, Contingency Reserve and RTC Ratios (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Statutory Accounting Practices [Line Items]
Statutory net income (loss)	$ 37,950	$ (20,136)	$ 15,233
Statutory surplus	899,476	894,331	449,602
Contingency reserve	1,036,639	768,324	531,825
Statutory capital	$ 1,936,115	$ 1,662,655	$ 981,427
Risk-to-capital (2)	12.0	11.6	15.8

Regulatory Information - Narrative (Details)		12 Months Ended
Regulatory Information - Narrative (Details)	Oct. 01, 2021 USD ($)	Dec. 31, 2021 USD ($) state	Nov. 29, 2021 USD ($)	Nov. 28, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019	Jan. 09, 2019
Statutory Accounting Practices [Line Items]
Number of states, in addition to wisconsin, with minimum statutory capital relative to RIF requirement \| state		15
Number of states which require minimum amount of statutory capital relative to risk in force \| state		16
Mortgage insurance risk in force		$ 22,300,000,000			$ 19,400,000,000
Risk-to-capital (2)		12.0			11.6	15.8
Mortgage insurance, percentage of indebtedness on single loan		25.00%					25.00%
Commutation fees	$ 8,400,000
Dividends, restriction with regards to capital surplus (in percent)		10.00%
Reinsurance, dividend distribution		$ 26,000,000
Dividends, restriction with regards to capital surplus		(1,600,000)
Reinsurance, extraordinary dividend distribution		$ 24,400,000
Maximum permitted RTC ratio		25
Revolving credit facility \| 2020 Revolving credit facility
Statutory Accounting Practices [Line Items]
Credit facility borrowing capacity		$ 250,000,000	$ 250,000,000	$ 110,000,000
Senior debt
Statutory Accounting Practices [Line Items]
Debt instrument face amount		$ 400,000,000

Quarterly Financial Data (Unaudited) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Quarterly Financial Information Disclosure [Abstract]
Net premiums earned	$ 113,933	$ 113,594	$ 110,888	$ 105,879	$ 100,709	$ 98,802	$ 98,944	$ 98,717	$ 444,294	$ 397,172	$ 345,015
Net investment income	10,045	9,831	9,382	8,814	8,386	8,337	7,070	8,104	38,072	31,897	30,856
Net realized investment gains	714	3	12	0	295	(4)	711	(72)	729	930	45
Other revenues	380	613	483	501	513	648	1,223	900	1,977	3,284	2,855
Insurance claims and claim expenses (benefit)	(500)	3,204	4,640	4,962	3,549	15,667	34,334	5,697	12,305	59,247	12,507
Underwriting and operating expenses	38,843	34,669	34,725	34,065	34,994	33,969	30,370	32,277	142,303	131,610	126,621
Service expenses	650	787	481	591	459	557	1,090	734	2,509	2,840	2,248
Interest expense	8,029	7,930	7,922	7,915	7,906	7,796	5,941	2,744	31,796	24,387	12,085
Loss (gain) from change in fair value of warrant liability	(112)	0	(658)	205	1,379	437	1,236	(5,959)		(2,907)	8,657
Income before income taxes	78,162	77,451	73,655	67,456	61,616	49,357	34,977	72,156	296,725	218,106	216,653
Income tax expense	17,639	17,258	16,133	14,565	13,348	11,178	8,129	13,885	65,595	46,540	44,696
Net income	$ 60,523	$ 60,193	$ 57,522	$ 52,891	$ 48,268	$ 38,179	$ 26,848	$ 58,271	$ 231,130	$ 171,566	$ 171,957
Income per share
Basic earnings per share (in dollars per share)	$ 0.71	$ 0.70	$ 0.67	$ 0.62	$ 0.57	$ 0.45	$ 0.36	$ 0.85	$ 2.70	$ 2.20	$ 2.54
Diluted earnings per share (in dollars per share)	$ 0.69	$ 0.69	$ 0.65	$ 0.61	$ 0.56	$ 0.45	$ 0.36	$ 0.74	$ 2.65	$ 2.13	$ 2.47
Weighted average common shares outstanding - basic (in shares)	85,757	85,721	85,647	85,317	84,956	84,805	73,617	68,563	85,620	78,023	67,573
Weighted average common shares outstanding - diluted (in shares)	87,117	86,880	86,819	86,487	86,250	85,599	74,174	70,401	86,885	79,263	69,721

Subsequent Event (Details)	Feb. 10, 2022 USD ($)
Subsequent Event \| February 2022 Share Repurchase Program
Subsequent Event [Line Items]
Share repurchase program, authorized amount	$ 125,000,000

SCHEDULE I - SUMMARY OF INVESTMENTS - OTHER THAN INVESTMENTS IN RELATED PARTIES (Details) $ in Thousands	Dec. 31, 2021 USD ($)
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Amortized Cost	$ 2,078,773
Fair Value	2,085,931
Amount Reflected on Balance Sheet	2,085,931
U.S. Treasury securities and obligations of U.S. government agencies
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Amortized Cost	29,443
Fair Value	30,424
Amount Reflected on Balance Sheet	30,424
Municipal debt securities
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Amortized Cost	553,793
Fair Value	554,078
Amount Reflected on Balance Sheet	554,078
Corporate debt securities
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Amortized Cost	1,388,204
Fair Value	1,393,830
Amount Reflected on Balance Sheet	1,393,830
Asset-backed securities
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Amortized Cost	96,324
Fair Value	96,581
Amount Reflected on Balance Sheet	96,581
Total bonds
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Amortized Cost	2,067,764
Fair Value	2,074,913
Amount Reflected on Balance Sheet	2,074,913
Short-term investments
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Amortized Cost	11,009
Fair Value	11,018
Amount Reflected on Balance Sheet	$ 11,018

SCHEDULE II - FINANCIAL INFORMATION OF REGISTRANT- PARENT COMPANY ONLY - Balance Sheets - Parent Company Only (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Apr. 30, 2012
Assets
Fixed maturities, available-for-sale, at fair value (amortized cost of $2,078,773 and $1,730,835 as of December 31, 2021 and December 31, 2020, respectively)	$ 2,085,931	$ 1,804,286
Cash and cash equivalents	76,646	126,937	$ 41,089	$ 25,294
Accrued investment income	11,900	9,862
Prepaid expenses	3,530	3,292
Software and equipment, net	32,047	29,665
Other assets	94,238	53,188
Total assets	2,450,581	2,166,666
Liabilities
Debt	394,623	393,301
Accounts payable and accrued expenses	72,000	61,716
Warrant liability, at fair value	2,363	4,409			$ 5,100
Deferred tax liability, net	164,175	112,586
Other liabilities	3,245	7,026
Total liabilities	884,795	797,075
Shareholders' equity
Common stock - class A shares, $0.01 par value; 85,792,849 and 85,163,039 shares issued and outstanding as of December 31, 2021 and December 31, 2020, respectively (250,000,000 shares authorized)	858	852
Additional paid-in capital	955,302	937,872
Accumulated other comprehensive income, net of tax	1,485	53,856
Retained earnings	608,141	377,011
Total shareholders' equity	1,565,786	1,369,591	930,420	701,500
Total liabilities and shareholders' equity	2,450,581	2,166,666
Parent
Assets
Fixed maturities, available-for-sale, at fair value (amortized cost of $2,078,773 and $1,730,835 as of December 31, 2021 and December 31, 2020, respectively)	84,854	52,867
Cash and cash equivalents	21,181	19,146	$ 13,431	$ 12,345
Investment in subsidiaries, at equity in net assets	1,951,124	1,724,360
Accrued investment income	367	263
Prepaid expenses	2,983	2,912
Due from affiliates, net	86,366	76,892
Software and equipment, net	32,047	29,665
Other assets	4,251	5,676
Total assets	2,183,173	1,911,781
Liabilities
Debt	394,623	393,301
Accounts payable and accrued expenses	42,246	30,802
Warrant liability, at fair value	2,363	4,409
Deferred tax liability, net	175,254	108,424
Other liabilities	2,901	5,254
Total liabilities	617,387	542,190
Shareholders' equity
Common stock - class A shares, $0.01 par value; 85,792,849 and 85,163,039 shares issued and outstanding as of December 31, 2021 and December 31, 2020, respectively (250,000,000 shares authorized)	858	852
Additional paid-in capital	955,302	937,872
Accumulated other comprehensive income, net of tax	1,485	53,856
Retained earnings	608,141	377,011
Total shareholders' equity	1,369,591	1,369,591
Total liabilities and shareholders' equity	$ 2,183,173	$ 1,911,781

SCHEDULE II - FINANCIAL INFORMATION OF REGISTRANT- PARENT COMPANY ONLY - Balance Sheets Additional Information - Parent Company Only (Details) - $ / shares	Dec. 31, 2021	Dec. 31, 2020
Condensed Balance Sheet Statements, Captions [Line Items]
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, issued (in shares)	85,792,849	85,163,039
Common stock, outstanding (in shares)	85,792,849	85,163,039
Common stock, authorized (in shares)	250,000,000	250,000,000
Parent
Condensed Balance Sheet Statements, Captions [Line Items]
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, issued (in shares)	85,792,849	85,163,039
Common stock, outstanding (in shares)	85,792,849	85,163,039
Common stock, authorized (in shares)	250,000,000	250,000,000

SCHEDULE II - FINANCIAL INFORMATION OF REGISTRANT- PARENT COMPANY ONLY - Statement of Operations - Parent Company Only (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Revenues
Net investment income	$ 10,045	$ 9,831	$ 9,382	$ 8,814	$ 8,386	$ 8,337	$ 7,070	$ 8,104	$ 38,072	$ 31,897	$ 30,856
Net realized investment gains	714	3	12	0	295	(4)	711	(72)	729	930	45
Total revenues									485,072	433,283	378,771
Expenses
Interest expense	8,029	7,930	7,922	7,915	7,906	7,796	5,941	2,744	31,796	24,387	12,085
(Gain) loss from change in fair value of warrant liability	(112)	0	(658)	205	1,379	437	1,236	(5,959)		(2,907)	8,657
Total expenses									188,347	215,177	162,118
Income before income taxes	78,162	77,451	73,655	67,456	61,616	49,357	34,977	72,156	296,725	218,106	216,653
Income tax expense	17,639	17,258	16,133	14,565	13,348	11,178	8,129	13,885	65,595	46,540	44,696
Net income	$ 60,523	$ 60,193	$ 57,522	$ 52,891	$ 48,268	$ 38,179	$ 26,848	$ 58,271	231,130	171,566	171,957
Other comprehensive (loss) income, net of tax:
Unrealized (losses) gains in accumulated other comprehensive (loss) income, net of tax (benefit) expense of $(95), $25, and $82 for each of the years in the three-year period ended December 31, 2021, respectively									(51,795)	35,829	32,155
Reclassification adjustment for gains included in net income, net of tax expense of $2, $5 and $0 for each of the years in the three-year period ended December 31, 2021, respectively									(576)	739	(35)
Other comprehensive (loss) income, net of tax									(52,371)	36,568	32,120
Comprehensive income									178,759	208,134	204,077
Parent
Revenues
Net investment income									327	398	1,124
Net realized investment gains									10	23	1
Total revenues									337	421	1,125
Expenses
Other operating expenses									8,264	9,262	11,714
Interest expense									68	0	0
(Gain) loss from change in fair value of warrant liability									(566)	(2,907)	8,657
Total expenses									7,766	6,355	20,371
Equity in net income of subsidiaries									303,970	217,134	226,480
Income before income taxes									296,541	211,200	207,234
Income tax expense									65,411	39,634	35,277
Net income									231,130	171,566	171,957
Other comprehensive (loss) income, net of tax:
Unrealized (losses) gains in accumulated other comprehensive (loss) income, net of tax (benefit) expense of $(95), $25, and $82 for each of the years in the three-year period ended December 31, 2021, respectively									(357)	94	308
Reclassification adjustment for gains included in net income, net of tax expense of $2, $5 and $0 for each of the years in the three-year period ended December 31, 2021, respectively									(8)	(18)	0
Equity in other comprehensive (loss) income of subsidiaries									(52,006)	36,492	31,812
Other comprehensive (loss) income, net of tax									(52,371)	36,568	32,120
Comprehensive income									$ 178,759	$ 208,134	$ 204,077

SCHEDULE II - FINANCIAL INFORMATION OF REGISTRANT- PARENT COMPANY ONLY - Statement of Operations Additional Information - Parent Company Only (Details) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Condensed Income Statements, Captions [Line Items]
Net unrealized (losses) gains in accumulated other comprehensive income, tax (benefit) expense	$ (13,768,000)	$ 9,525,000	$ 8,548,000
Reclassification adjustment for realized losses (gains) included in net income, tax expense (benefit)	153,000	(196,000)	9,000
Parent
Condensed Income Statements, Captions [Line Items]
Net unrealized (losses) gains in accumulated other comprehensive income, tax (benefit) expense	(95,000)	25,000	82,000
Reclassification adjustment for realized losses (gains) included in net income, tax expense (benefit)	$ 2,000	$ 5,000	$ 0

SCHEDULE II - FINANCIAL INFORMATION OF REGISTRANT- PARENT COMPANY ONLY - Statements of Cash Flows - Parent Company Only (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Cash flows from operating activities
Net income	$ 60,523	$ 60,193	$ 57,522	$ 52,891	$ 48,268	$ 38,179	$ 26,848	$ 58,271	$ 231,130	$ 171,566	$ 171,957
Adjustments to reconcile net income to net cash provided by operating activities:
(Gain) loss from change in fair value of warrant liability									(566)	(2,907)	8,657
Net realized investment gains									(729)	(930)	(45)
Depreciation and amortization									11,232	9,930	9,299
Amortization of debt discount and debt issuance costs									1,861	4,036	1,011
Deferred income taxes									65,510	46,506	45,082
Share-based compensation expense									16,678	11,115	13,031
Changes in operating assets and liabilities:
Accrued investment income									(2,038)	(3,031)	(1,137)
Prepaid expenses									(238)	220	(472)
Other assets									(42,833)	(38,804)	(8,831)
Accounts payable and accrued expenses									16,908	18,072	3,888
Net cash provided by operating activities									325,719	252,598	208,150
Cash flows from investing activities
Purchase of short-term investments									(10,640)	(42,241)	(230,362)
Purchase of fixed-maturity investments, available-for-sale									(514,405)	(1,065,916)	(290,533)
Proceeds from maturity of short-term investments									0	86,045	244,921
Proceeds from redemptions, maturities and sale of fixed-maturity investments, available-for-sale									163,103	404,717	91,575
Software and equipment									(12,238)	(12,159)	(9,956)
Net cash used in investing activities									(374,180)	(629,554)	(194,355)
Cash flows from financing activities
Proceeds from issuance of common stock related to public offering, net of issuance costs									0	219,687	0
Proceeds from issuance of common stock related to employee equity plans									4,201	8,871	21,748
Proceeds from issuance of common stock related to warrant exercises									503	0	0
Taxes paid related to net share settlement of equity awards									(5,426)	(8,961)	(18,248)
Payments of debt issuance costs									(1,108)	(9,043)	0
Net cash (used in) provided by financing activities									(1,830)	462,804	2,000
Net (decrease) increase in cash, cash equivalents and restricted cash									(50,291)	85,848	15,795
Cash, cash equivalents and restricted cash, beginning of period				126,937				41,089	126,937	41,089	25,294
Cash, cash equivalents and restricted cash, end of period	76,646				126,937				76,646	126,937	41,089
Stockholders' Equity Attributable to Parent	(1,565,786)				(1,369,591)				(1,565,786)	(1,369,591)	(930,420)	$ (701,500)
Retained Earnings
Cash flows from operating activities
Net income									231,130	171,566	171,957
Cash flows from financing activities
Stockholders' Equity Attributable to Parent	(608,141)				(377,011)				(608,141)	(377,011)	(205,445)	$ (33,488)
Parent
Cash flows from operating activities
Net income									231,130	171,566	171,957
Adjustments to reconcile net income to net cash provided by operating activities:
(Gain) loss from change in fair value of warrant liability									(566)	(2,907)	8,657
Net realized investment gains									(10)	(23)	(1)
Depreciation and amortization									801	807	286
Amortization of debt discount and debt issuance costs									1,861	4,036	1,011
Deferred income taxes									66,941	45,483	44,030
Share-based compensation expense									16,678	11,115	13,031
Changes in operating assets and liabilities:
Investment in subsidiaries, at equity in net assets									(302,165)	(217,134)	(226,480)
Accrued investment income									(104)	(44)	(3)
Receivable from affiliates									(9,474)	(14,651)	(20,902)
Prepaid expenses									(71)	420	(409)
Other assets									(425)	(336)	165
Accounts payable and accrued expenses									10,068	4,592	(1,640)
Net cash provided by operating activities									14,664	2,924	(10,298)
Cash flows from investing activities
Capitalization of subsidiaries									(800)	(445,448)	(800)
Purchase of short-term investments									(10,640)	(19,897)	(104,192)
Purchase of fixed-maturity investments, available-for-sale									(2,797)	(53,504)	(2,186)
Proceeds from maturity of short-term investments									0	41,228	111,539
Proceeds from redemptions, maturities and sale of fixed-maturity investments, available-for-sale									4,464	20,241	5,877
Software and equipment									(1,026)	(2,633)	(854)
Net cash used in investing activities									(10,799)	(460,013)	9,384
Cash flows from financing activities
Proceeds from issuance of common stock related to public offering, net of issuance costs									0	219,687	0
Proceeds from issuance of common stock related to employee equity plans									4,201	8,871	21,748
Proceeds from issuance of common stock related to warrant exercises									503	0	0
Taxes paid related to net share settlement of equity awards									(5,426)	(8,961)	(18,248)
Proceeds from senior secured notes									0	400,000	0
Repayments of term loan									0	(147,750)	(1,500)
Payments of debt issuance costs									(1,108)	(9,043)	0
Net cash (used in) provided by financing activities									(1,830)	462,804	2,000
Net (decrease) increase in cash, cash equivalents and restricted cash									2,035	5,715	1,086
Cash, cash equivalents and restricted cash, beginning of period				$ 19,146				$ 13,431	19,146	13,431	12,345
Cash, cash equivalents and restricted cash, end of period	21,181				19,146				21,181	19,146	$ 13,431
Stockholders' Equity Attributable to Parent	$ (1,369,591)				$ (1,369,591)				$ (1,369,591)	$ (1,369,591)

SCHEDULE II - FINANCIAL INFORMATION OF REGISTRANT- PARENT COMPANY ONLY - Supplemental Notes - Parent Company Only (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Condensed Financial Statements, Captions [Line Items]
Reinsurance, dividend distribution	$ 26.0
Dividends, restriction with regards to capital surplus	1.6
Reinsurance, extraordinary dividend distribution	24.4
Subsidiaries
Condensed Financial Statements, Captions [Line Items]
Restricted net assets less aggregate dividend capacity	2,000.0	$ 1,700.0
Operating underwriting and operating expenses	$ 149.4	$ 152.9	$ 117.1

SCHEDULE IV - FINANCIAL INFORMATION OF REGISTRANT REINSURANCE (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
SEC Schedule, 12-17, Insurance Companies, Reinsurance [Line Items]
Gross Amount										$ 472,998	$ 398,303
Ceded to Other Companies									$ 92,336	75,826	53,288
Net premiums earned	$ 113,933	$ 113,594	$ 110,888	$ 105,879	$ 100,709	$ 98,802	$ 98,944	$ 98,717	444,294	397,172	345,015
Parent
SEC Schedule, 12-17, Insurance Companies, Reinsurance [Line Items]
Gross Amount									536,630	472,998	398,303
Ceded to Other Companies									92,336	75,826	53,288
Assumed from Other Companies									0	0	0
Net premiums earned									$ 444,294	$ 397,172	$ 345,015
Percentage of Amount Assumed to Net									0.00%	0.00%	0.00%