0001547903-26-000029 | 10-Q | XBRL Viewer

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Earnings per Share (EPS) - Schedule of Earnings Per Share, Basic and Diluted (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Basic EPS
Net income - basic	$ 99,330	$ 102,559
Net income - diluted	$ 99,330	$ 102,559
Basic weighted average shares outstanding (in shares)	76,175	78,407
Dilutive effect of issuable shares (in shares)	1,260	1,451
Dilutive weighted average shares outstanding (in shares)	77,435	79,858
Basic earnings per share (in dollars per share)	$ 1.30	$ 1.31
Diluted earnings per share (in dollars per share)	$ 1.28	$ 1.28
Anti-dilutive shares (in shares)	6	0

- Definition

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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+ Details

- Definition

The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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+ Details

- Definition

Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities; of income (loss) available to common shareholders.

+ References

+ Details

- Definition

Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities, and addition from assumption of issuance of common shares for dilutive potential common shares; of income (loss) available to common shareholders.

+ References + Details

Organization, Basis of Presentation and Summary of Accounting Principles	3 Months Ended
	Mar. 31, 2026
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization, Basis of Presentation and Summary of Accounting Principles	Organization, Basis of Presentation and Summary of Accounting Principles 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. We operate as a single segment for the purposes of assessing performance and making operating decisions. Basis of Presentation The accompanying unaudited condensed consolidated financial statements, which include the results of NMIH and its wholly-owned subsidiaries, have been prepared in accordance with the instructions to Form 10-Q as prescribed by the SEC for interim reporting and include other information and disclosures required by accounting principles generally accepted in the U.S. (GAAP). Our accounts are maintained in U.S. dollars. These statements should be read in conjunction with our consolidated financial statements and notes thereto for the year ended December 31, 2025, included in our 2025 10-K. All intercompany transactions have been eliminated. The preparation of financial statements in accordance with GAAP requires management to make estimates and assumptions that affect reported amounts of assets and liabilities, and the disclosure of contingent assets and liabilities as of the balance sheet date, as well as reported amounts of income and expenses for the reporting period. Actual results could differ from those estimates. In the opinion of management, these unaudited condensed consolidated financial statements include all adjustments (including normal recurring adjustments) that are necessary to present a fair statement of financial position, results of operations and cash flows for the periods presented. The results of operations for the interim period may not be indicative of the results that may be expected for the full year ending December 31, 2026. Significant Accounting Principles There have been no changes to our significant accounting principles as described in Item 8, “Financial Statements and Supplementary Data - Notes to Consolidated Financial Statements - Note 2 - Summary of Accounting Principles” of our 2025 10-K. Recent Accounting Pronouncements – Not Yet Adopted In November 2024, the FASB issued ASU 2024-03, Disaggregation of Income Statement Expense (Topic 220). The update expands disclosure requirements related to certain income statement expenses, including a requirement to provide a tabular disaggregation of certain operating expenses by category. The standard will take effect for all public business entities for annual reporting periods beginning after December 15, 2026, and interim reporting periods beginning after December 15, 2027. Early adoption is permitted. We are currently evaluating the impact the adoption of this ASU will have, if any, on our consolidated financial statements. In September 2025, the FASB issued ASU 2025-06, Targeted Accounting for Internal-Use Software (Topic 350). The update clarifies the criteria surrounding the capitalization of certain costs and expands related disclosure requirements. The standard will take effect for all public business entities for annual reporting periods beginning after December 15, 2027, and interim reporting periods within those annual reporting periods. Early adoption is permitted. We are currently evaluating the impact the adoption of this ASU will have, if any, on our consolidated financial statements.

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Cash flows from operating activities
Net income	$ 99,330	$ 102,559
Adjustments to reconcile net income to net cash provided by operating activities:
Net realized investment losses (gains)	147	(24)
Depreciation and amortization	2,481	2,888
Net accretion of discount on investment securities	(707)	(770)
Amortization of debt discount and debt issuance costs	623	592
Deferred income taxes	18,857	24,543
Share-based compensation expense	4,682	4,507
Changes in operating assets and liabilities:
Premiums receivable, net	(602)	(1,349)
Accrued investment income	(2,473)	(1,255)
Deferred policy acquisition costs, net	42	314
Reinsurance recoverable	(1,126)	881
Other assets	(2,319)	(555)
Unearned premiums	(2,980)	(6,041)
Reserve for insurance claims and claim expenses	14,775	(224)
Reinsurance balances, net	0	(118)
Accounts payable and accrued expenses	(14,639)	(24,797)
Net cash provided by operating activities	116,091	101,151
Cash flows from investing activities
Purchase of fixed-maturity investments, available-for-sale	(299,673)	(141,474)
Proceeds from maturities of short-term investments	61,625	55,100
Proceeds from maturities and redemptions of fixed-maturity investments, available-for-sale	76,208	40,423
Proceeds from sales of fixed-maturity investments, available-for-sale	115,032	0
Additions to software and equipment	(1,100)	(1,706)
Net cash used in investing activities	(47,908)	(47,657)
Cash flows from financing activities
Proceeds from issuance of common stock related to employee equity plans	3,881	2,778
Taxes paid related to net share settlement of equity awards	(17,647)	(10,428)
Repurchases of common stock	(27,675)	(25,943)
Net cash used in financing activities	(41,441)	(33,593)
Net increase in cash, cash equivalents and restricted cash	26,742	19,901
Cash, cash equivalents and restricted cash, beginning of period	43,937	54,308
Cash, cash equivalents and restricted cash, end of period	70,679	74,209
Supplemental disclosures of cash flow information
Interest paid	12,750	18,700
Income taxes refunded	$ 32	$ 0

Segment Reporting (Details) $ in Thousands	3 Months Ended
Segment Reporting (Details) $ in Thousands	Mar. 31, 2026 USD ($) segment	Mar. 31, 2025 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments \| segment	1
Interest revenue	$ 28,953	$ 24,035
Amortization and depreciation expense	2,481	2,888
Mortgage Insurance Segment
Segment Reporting Information [Line Items]
Interest revenue	29,000	24,000
Amortization and depreciation expense	$ 2,500	$ 2,900

Reserves for Insurance Claims and Claim Expenses

3 Months Ended

Mar. 31, 2026

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 March 31, 2026, we held gross reserves for insurance claims and claim expenses of $211.2 million. During the three months ended March 31, 2026, we paid 170 claims totaling $10.8 million, including 164 claims covered under the QSR Transactions representing $2.1 million of ceded claims and claim expenses.

We had 8,044 loans in default in our primary insured portfolio as of March 31, 2026, which represented a 1.17% default rate against 684,977 total policies in-force, and 7,661 loans in default in our primary insured portfolio as of December 31, 2025, which represented a 1.12% default rate against 684,058 total policies in-force. 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.

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


	For the three months ended March 31,
	2026		2025
	(In Thousands)
Beginning balance	$	196,429	$	152,071
Less reinsurance recoverables (1)	(38,577)		(32,260)
Beginning balance, net of reinsurance recoverables	157,852		119,811

Add claims incurred:
Claims and claim expenses incurred:
Current year (2)	47,150		34,559
Prior years (3)	(26,489)		(30,081)
Total claims and claim expenses incurred	20,661		4,478

Less claims paid:
Claims and claim expenses paid:
Current year (2)	—		—
Prior years (3)	8,682		4,076
Reinsurance terminations (4)	(1,670)		(255)
Total claims and claim expenses paid	7,012		3,821

Reserve at end of period, net of reinsurance recoverables	171,501		120,468
Add reinsurance recoverables (1)	39,703		31,379
Ending balance	$	211,204	$	151,847

(1) Related to ceded losses recoverable under the QSR Transactions. See Note 5, “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 $34.8 million attributed to net case reserves and $11.7 million attributed to net IBNR reserves for the three months ended March 31, 2026 and $25.9 million attributed to net case reserves and $8.1 million attributed to net IBNR reserves for the three months ended March 31, 2025.

(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 $15.2 million attributed to net case reserves and $10.8 million attributed to net IBNR reserves for the three months ended March 31, 2026 and $21.8 million attributed to net case reserves and $8.1 million attributed to net IBNR reserves for the three months ended March 31, 2025.

(4) Represents the settlement of reinsurance recoverables in conjunction with the termination or amendment of certain QSR Transactions.

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. The amount of claims incurred relating to current year defaults increased during the three months ended March 31, 2026 compared to the three months ended March 31, 2025, primarily due to an increase in the total number of new delinquencies emerging during the period tied to the growth and natural seasoning of our portfolio, and an increase in the average case reserves established against newly defaulted loans. Our provision for claims and claim expenses during both the three months ended March 31, 2026 and 2025 benefited from favorable development on prior year defaults. We recognized $26.5 million and $30.1 million of favorable prior year development during the three months ended March 31, 2026 and 2025, respectively, primarily due to cure activity and ongoing analysis of recent loss development trends. 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 $153.0 million related to prior year defaults remained as of March 31, 2026.

Reinsurance (Tables)

3 Months Ended

Mar. 31, 2026

Reinsurance Disclosures [Abstract]

Schedule of Effect of Reinsurance Agreements on Premiums Written and Earned

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


	For the three months ended March 31,
		2026		2025
		(In Thousands)
Net premiums written
Direct		$	186,006	$	174,415
Ceded (1)		(34,180)		(31,029)
Net premiums written		$	151,826	$	143,386

Net premiums earned
Direct		$	188,986	$	180,456
Ceded (1)		(34,180)		(31,090)
Net premiums earned		$	154,806	$	149,366

(1) Net of profit commission.

The following table presents the inception date, covered production period, ceding commission and profit commission for each outstanding QSR Transaction. Current amounts are presented as of March 31, 2026.

Inception Date

Covered Production

Ceding Percentage

Ceding Commission

Profit Commission

2018 QSR

1/1/2018

1/1/2018 – 12/31/2018

1/1/2019 – 12/31/2019

16%

13% (1)

42%

up to 45%

2020 QSR

4/1/2020

4/1/2020 – 12/31/2020

21%

45%

up to 45%

2021 QSR

1/1/2021

1/1/2021 – 10/30/2021

20%

35%

up to 54%

2022 QSR

10/1/2021

10/30/2021 – 12/31/2022

20%

up to 68%

2022 Seasoned QSR

7/1/2022

1/1/2013 – 12/31/2016

7/1/2019 –3/31/2020

48% (2)

53%

up to 38%

2023 QSR

1/1/2023

1/1/2023 – 12/31/2023

20%

up to 63%

2024 QSR

1/1/2024

1/1/2024 – 12/31/2024

20%

up to 56%

2025 QSR

1/1/2025

1/1/2025 – 12/31/2025

20%

up to 62%

2026 QSR

1/1/2026

1/1/2026 – 12/31/2026

25%

21%

up to 61%

(1) Under the terms of the 2018 QSR Transaction, NMIC cedes premiums earned related to 16% of the risk on eligible policies written in 2018 and 13% of the risk on eligible policies written in 2019.

(2) Under the terms of the 2022 Seasoned QSR Transaction, NMIC cedes premiums earned related to 48% of the risk on eligible policies after the consideration of coverage provided under any other QSR Transaction.

The following table shows amounts related to the QSR Transactions:


	As of and for the three months ended
		March 31, 2026		March 31, 2025
		(In Thousands)
Ceded risk-in-force		$	12,189,562	$	12,888,870
Ceded premiums earned		(37,930)		(41,011)
Ceded claims and claim expenses		4,890		523
Ceding commission earned		10,205		9,768
Profit commission		17,131		23,398

Schedule of XOL Transactions

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 outstanding XOL Transaction. Current amounts are presented as of March 31, 2026.


($ values in thousands)	Inception Date	Covered Production	Initial Reinsurance Coverage		Current Reinsurance Coverage		Initial First Layer Retained Loss		Current First Layer Retained Loss (1)
2022-1 XOL	April 1, 2022	10/1/2021 – 3/31/2022	$	289,741	$	137,567	$	133,366	$	128,264
2022-2 XOL	July 1, 2022	4/1/2022 – 6/30/2022	154,306		109,595		78,906		72,011
2022-3 XOL	October 1, 2022	7/1/2022 – 9/30/2022	96,779		70,905		106,265		100,303
2023-1 XOL	January 1, 2023	10/1/2022 – 6/30/2023	89,864		59,249		146,513		140,573
2023-2 XOL	July 1, 2023	7/1/2023 – 12/31/2023	100,777		57,358		136,875		134,382
2024 XOL	January 1, 2024	1/1/2024 – 12/31/2024	162,500		143,357		312,172		310,606
2025 XOL	January 1, 2025	1/1/2025 – 12/31/2025	283,849		275,896		321,331		321,331
2026-1 XOL(2)	January 1, 2026	1/1/2026 – 12/31/2026	42,371		42,371		76,881		76,881

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

(2) The initial reinsurance coverage, current reinsurance coverage, initial first layer retained loss and current first layer retained loss for the 2026-1 XOL Transaction will increase as incremental covered production is ceded under the transaction through December 31, 2026.

Schedule of ILN Transactions

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 outstanding ILN Transaction. Current amounts are presented as of March 31, 2026.


($ values in thousands)	Inception Date	Covered Production	Initial Reinsurance Coverage		Current Reinsurance Coverage		Initial First Layer Retained Loss		Current First Layer Retained Loss (1)





2021-1 ILN (4)	April 27, 2021	10/1/2020 – 3/31/2021 (2)	$	367,238	$	71,735	$	163,708	$	161,975
2021-2 ILN	October 26, 2021	4/1/2021 – 9/30/2021 (3)	363,596		163,111		146,229		143,359

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

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

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

(4) Effective April 27, 2026, NMIC exercised its optional call to terminate a reinsurance agreement with and the associated insurance-linked notes issued by Oaktown Re VI Ltd. In connection with the termination, NMIC's excess of loss reinsurance agreement with Oaktown Re VI Ltd. was commuted and the insurance-linked notes issued by Oaktown Re VI Ltd. were redeemed in full with a distribution of remaining collateral assets.

Investments - Schedule of Fair Values and Gross Unrealized Gains and Losses (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 3,255,203	$ 3,190,174
Gross Unrealized, Gains	16,053	33,125
Gross Unrealized, Losses	(97,149)	(86,276)
Fair Value	3,174,107	3,137,023
U.S. Treasury securities and obligations of U.S. government agencies
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	259,668	306,168
Gross Unrealized, Gains	1,328	2,544
Gross Unrealized, Losses	(3,812)	(1,684)
Fair Value	257,184	307,028
Municipal debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	621,318	635,396
Gross Unrealized, Gains	1,603	3,052
Gross Unrealized, Losses	(27,656)	(26,879)
Fair Value	595,265	611,569
Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,210,982	2,047,122
Gross Unrealized, Gains	13,083	27,504
Gross Unrealized, Losses	(62,318)	(55,015)
Fair Value	2,161,747	2,019,611
U.S. agency mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	40,925	42,109
Gross Unrealized, Gains	0	10
Gross Unrealized, Losses	(349)	(48)
Fair Value	40,576	42,071
Other asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	96,926	72,774
Gross Unrealized, Gains	39	0
Gross Unrealized, Losses	(3,014)	(2,649)
Fair Value	93,951	70,125
Total bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	3,229,819	3,103,569
Gross Unrealized, Gains	16,053	33,110
Gross Unrealized, Losses	(97,149)	(86,275)
Fair Value	3,148,723	3,050,404
Short-term investments
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	25,384	86,605
Gross Unrealized, Gains	0	15
Gross Unrealized, Losses		(1)
Fair Value	$ 25,384	$ 86,619

Reinsurance - Schedule of Amounts Related to QSR Transactions (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Ceded Credit Risk [Line Items]
Ceded premiums earned	$ (34,180)	$ (31,090)
Third-party Reinsurers
Ceded Credit Risk [Line Items]
Ceded risk-in-force	12,189,562	12,888,870
Ceded premiums earned	(37,930)	(41,011)
Ceded claims and claim expenses	4,890	523
Ceding commission earned	10,205	9,768
Profit commission	$ 17,131	$ 23,398

- Definition

Amount of earned premiums ceded to other entities.

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+ Details

Investments - Schedule of Net Investment Income (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Investment Income, Net [Abstract]
Investment income	$ 28,953	$ 24,035
Investment expenses	(349)	(349)
Net investment income	28,604	23,686
Cash and Cash Equivalents
Investment Income, Net [Abstract]
Investment income	$ 900	$ 900

Reinsurance - Schedule of Effect of Reinsurance Agreements on Premiums Written and Earned (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Net premiums written
Direct	$ 186,006	$ 174,415
Ceded	(34,180)	(31,029)
Net premiums written	151,826	143,386
Net premiums earned
Direct	188,986	180,456
Ceded	(34,180)	(31,090)
Net premiums earned	$ 154,806	$ 149,366

- Definition

Amount of earned premiums ceded to other entities.

+ References

+ Details

- Definition

Amount, before premiums ceded to other entities and premiums assumed by the entity, of premiums earned.

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Amount, after premiums ceded to other entities and premiums assumed by the entity, of premiums earned.

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Fair Value of Financial Instruments -Schedule of Fair Value Measurements of Financial Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of securities	$ 3,174,107	$ 3,137,023
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 of securities	257,184	307,028
Municipal debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of securities	595,265	611,569
Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of securities	2,161,747	2,019,611
U.S. agency mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of securities	40,576	42,071
Other asset-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of securities	93,951	70,125
Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash, cash equivalents and short-term investments	96,063	130,556
Total assets	3,244,786	3,180,960
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 of securities	257,184	307,028
Recurring \| Municipal debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of securities	595,265	611,569
Recurring \| Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of securities	2,161,747	2,019,611
Recurring \| U.S. agency mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of securities	40,576	42,071
Recurring \| Other asset-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of securities	93,951	70,125
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	96,063	130,556
Total assets	353,247	437,584
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 of securities	257,184	307,028
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 of securities	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 of securities	0	0
Recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| U.S. agency mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of securities	0	0
Recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| Other asset-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of securities	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	2,891,539	2,743,376
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 of securities	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 of securities	595,265	611,569
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 of securities	2,161,747	2,019,611
Recurring \| Significant Other Observable Inputs (Level 2) \| U.S. agency mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of securities	40,576	42,071
Recurring \| Significant Other Observable Inputs (Level 2) \| Other asset-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of securities	93,951	70,125
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
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 of securities	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 of securities	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 of securities	0	0
Recurring \| Significant Unobservable Inputs (Level 3) \| U.S. agency mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of securities	0	0
Recurring \| Significant Unobservable Inputs (Level 3) \| Other asset-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of securities	$ 0	$ 0

Investments - Schedule of Net Realized Investment Gains (Losses) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Investments, Debt and Equity Securities [Abstract]
Gross realized investment gains	$ 1,046	$ 24
Gross realized investment losses	(1,193)	0
Net realized investment (losses) gains	$ (147)	$ 24

Investments

3 Months Ended

Mar. 31, 2026

Investments, Debt and Equity Securities [Abstract]

Investments

We hold all investments on an available-for-sale basis at fair value on our condensed consolidated balance sheets 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 recognize an impairment loss equivalent to the difference of the amortized cost basis of the security and its fair value through the condensed consolidated statements of operations and comprehensive income as a “Net Realized Investment Loss.” In the event of an impairment of a security that we intend to and have the ability to hold to maturity, we evaluate the drivers of the impairment to determine the portion that is credit related and the portion that is non-credit related. The portion of impairment loss that is attributed to credit related factors is recognized through the statement of operations as a provision for credit loss and the portion that is attributed to 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 March 31, 2026	(In Thousands)
U.S. Treasury securities and obligations of U.S. government agencies	$	259,668	$	1,328	$	(3,812)	$	257,184
Municipal debt securities	621,318		1,603		(27,656)		595,265
Corporate debt securities	2,210,982		13,083		(62,318)		2,161,747
U.S. agency mortgage-backed securities (1)	40,925		—		(349)		40,576
Other asset-backed securities	96,926		39		(3,014)		93,951
Total bonds	3,229,819		16,053		(97,149)		3,148,723
Short-term investments	25,384		—		*		25,384
Total investments	$	3,255,203	$	16,053	$	(97,149)	$	3,174,107


	Amortized Cost		Gross Unrealized				Fair Value
			Gains		Losses
As of December 31, 2025	(In Thousands)
U.S. Treasury securities and obligations of U.S. government agencies	$	306,168	$	2,544	$	(1,684)	$	307,028
Municipal debt securities	635,396		3,052		(26,879)		611,569
Corporate debt securities	2,047,122		27,504		(55,015)		2,019,611
U.S. agency mortgage-backed securities (1)	42,109		10		(48)		42,071
Other asset-backed securities	72,774		—		(2,649)		70,125
Total bonds	3,103,569		33,110		(86,275)		3,050,404
Short-term investments	86,605		15		(1)		86,619
Total investments	$	3,190,174	$	33,125	$	(86,276)	$	3,137,023

(1) 100% of our U.S. agency mortgage-backed securities at March 31, 2026 and December 31, 2025 are guaranteed by Ginnie Mae which has the full faith and credit of the U.S. federal government.

* Amounts not identifiable due to rounding.

The following table presents a breakdown of the fair value of our corporate debt securities by issuer industry group as of March 31, 2026 and December 31, 2025:


	March 31, 2026		December 31, 2025
Financial	41	%	39	%
Consumer	27		28
Utilities	10		11
Industrial	9		9
Technology	6		6
Communications	5		6
Basic Materials	2		1
Total	100	%	100	%

As of both March 31, 2026 and December 31, 2025, approximately $5.4 million 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.

We periodically recognize unsettled trade receivables or payables in connection with our investing activity. Unsettled trade receivables represent funds due but not yet received for the sale or maturity of investments at period end. Unsettled trade payables represent funds due but not yet paid for investments purchased at period end. “Accounts Payable and Accrued Expenses” on our condensed consolidated balance sheets included $17.3 million of unsettled trade payables related to the purchase of certain investment securities at March 31, 2026. No unsettled trade receivables were outstanding at March 31, 2026. No unsettled trade payables were outstanding at December 31, 2025. Unsettled trade receivables were immaterial at December 31, 2025.

Scheduled Maturities

The amortized cost and fair value of available-for-sale securities as of March 31, 2026 and December 31, 2025, 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 U.S. agency mortgage-backed securities and other asset-backed securities provide for periodic payments throughout their lives, they are listed below in separate categories.


As of March 31, 2026	Amortized Cost		Fair Value
	(In Thousands)
Due in one year or less	$	266,378	$	264,645
Due after one through five years	1,672,647		1,619,527
Due after five through ten years	1,110,252		1,088,729
Due after ten years	68,075		66,679
U.S. agency mortgage-backed securities	40,925		40,576
Other asset-backed securities	96,926		93,951
Total investments	$	3,255,203	$	3,174,107


As of December 31, 2025	Amortized Cost		Fair Value
	(In Thousands)
Due in one year or less	$	292,846	$	292,232
Due after one through five years	1,713,613		1,672,123
Due after five through ten years	1,062,039		1,053,628
Due after ten years	6,793		6,844
U.S. agency mortgage-backed securities	42,109		42,071
Other asset-backed securities	72,774		70,125
Total investments	$	3,190,174	$	3,137,023

Aging of Unrealized Losses

As of March 31, 2026, the investment portfolio had gross unrealized losses of $97.1 million, of which $87.3 million were associated with securities that had been in an unrealized loss position for a period of twelve months or longer. As of December 31, 2025, the investment portfolio had gross unrealized losses of $86.3 million, of which $84.3 million were associated with securities that 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 March 31, 2026		($ In Thousands)
U.S. Treasury securities and obligations of U.S. government agencies	18	$	194,270	$	(3,804)	1	$	534	$	(8)	19	$	194,804	$	(3,812)
Municipal debt securities	2	9,386		(6)		211	462,436		(27,650)		213	471,822		(27,656)
Corporate debt securities	82	470,222		(5,391)		148	756,507		(56,927)		230	1,226,729		(62,318)
U.S. agency mortgage-backed securities	3	40,576		(349)		—	—		—		3	40,576		(349)
Other asset-backed securities	12	65,553		(272)		15	22,393		(2,742)		27	87,946		(3,014)
Short-term investments	1	24,998		*		—	—		—		1	24,998		*
Total	118	$	805,005	$	(9,822)	375	$	1,241,870	$	(87,327)	493	$	2,046,875	$	(97,149)


	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, 2025		($ In Thousands)
U.S. Treasury securities and obligations of U.S. government agencies	11	$	204,062	$	(1,673)	5	$	1,993	$	(11)	16	$	206,055	$	(1,684)
Municipal debt securities	—	—		—		215	477,095		(26,879)		215	477,095		(26,879)
Corporate debt securities	13	43,546		(209)		159	836,050		(54,806)		172	879,596		(55,015)
U.S. agency mortgage-backed securities	2	27,109		(48)		—	—		—		2	27,109		(48)
Other asset-backed securities	7	33,836		(53)		16	36,289		(2,596)		23	70,125		(2,649)
Short-term investments	1	24,778		(1)		—	—		—		1	24,778		(1)
Total	34	$	333,331	$	(1,984)	395	$	1,351,427	$	(84,292)	429	$	1,684,758	$	(86,276)

* Amounts not identifiable due to rounding.

Allowance for Credit Losses

As of March 31, 2026 and December 31, 2025, 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 three months ended March 31, 2026 or 2025.

We evaluated the securities in an unrealized loss position as of March 31, 2026, assessing their credit ratings as well as any adverse conditions specifically related to the security. Based upon our assessment of the amount and timing of cash flows to be collected over the remaining life of each instrument, we believe the unrealized losses as of March 31, 2026 are not indicative of the ultimate collectability of the current amortized cost of the securities. Rather, the unrealized losses on securities held as of March 31, 2026 were primarily driven by fluctuations in interest rates, and to a lesser extent, movements in credit spreads following the purchase of those securities.

Net Investment Income

The following table presents the components of net investment income:


	For the three months ended March 31,
		2026		2025
		(In Thousands)
Investment income (1)		$	28,953	$	24,035
Investment expenses		(349)		(349)
Net investment income		$	28,604	$	23,686

(1) Includes interest income recognized on cash and cash equivalents of $0.9 million during both the three months ended March 31, 2026 and 2025.

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


	For the three months ended March 31,
		2026		2025
		(In Thousands)
Gross realized investment gains		$	1,046	$	24
Gross realized investment losses		(1,193)		—
Net realized investment (losses) gains		$	(147)	$	24

Investments - Narrative (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Debt Securities, Available-for-sale [Line Items]
Payable for unsettled trade transactions	$ 17,300	$ 0
Receivable for unsettled trade transactions	0	0
Unrealized loss position, accumulated loss	97,149	86,276
Unrealized loss position, 12 months or greater	87,327	84,292
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	5,400	5,400
Unrealized loss position, accumulated loss	3,812	1,684
Unrealized loss position, 12 months or greater	$ 8	$ 11

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (aa)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (aaa)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

+ Details

Reinsurance - Narrative (Details) $ in Thousands	3 Months Ended
Reinsurance - Narrative (Details) $ in Thousands	Mar. 31, 2026 USD ($) quota_share_agreement reinsuranceAgreement	Mar. 31, 2025 USD ($)	Dec. 31, 2025 USD ($)	Dec. 31, 2024 USD ($)
Ceded Credit Risk [Line Items]
Number of quota share reinsurance treaties \| quota_share_agreement	9
Reinsurance recoverable on unpaid claims	$ 39,703	$ 31,379	$ 38,577	$ 32,260
Number of excess-of-loss reinsurance agreements \| reinsuranceAgreement	8
Reinsurance coverage amount	$ 11,000	10,200
Reinsurance coverage amount amortized (in percent)	10.00%
2026-2 XOL Transaction
Ceded Credit Risk [Line Items]
Reinsurance retention policy excess of loss reinsurance coverages	$ 148,000
2027 XOL Transaction
Ceded Credit Risk [Line Items]
Reinsurance retention policy excess of loss reinsurance coverages	$ 125,000
Minimum
Ceded Credit Risk [Line Items]
Reinsurance coverage, term of underlying mortgage amortization (in years)	10 years
Maximum
Ceded Credit Risk [Line Items]
Reinsurance coverage, term of underlying mortgage amortization (in years)	12 years 6 months
Reinsurance Policy, Type [Axis]: QSR Transactions
Ceded Credit Risk [Line Items]
Reinsurance recoverable on unpaid claims	$ 39,700		$ 38,600
Third-party Reinsurers \| Reinsurance Policy, Type [Axis]: 2018 QSR Transaction, Period 1
Ceded Credit Risk [Line Items]
Ceding Percentage	16.00%
Third-party Reinsurers \| Reinsurance Policy, Type [Axis]: 2018 QSR Transaction, Period 2
Ceded Credit Risk [Line Items]
Ceding Percentage	13.00%
Third-party Reinsurers \| Reinsurance Policy, Type [Axis]: 2020 QSR Transaction
Ceded Credit Risk [Line Items]
Ceding Percentage	21.00%
Third-party Reinsurers \| Reinsurance Policy, Type [Axis]: 2021 QSR Transaction
Ceded Credit Risk [Line Items]
Ceding Percentage	20.00%
Third-party Reinsurers \| Reinsurance Policy, Type [Axis]: 2022 QSR Transaction
Ceded Credit Risk [Line Items]
Ceding Percentage	20.00%
Third-party Reinsurers \| Reinsurance Policy, Type [Axis]: 2022 Seasoned QSR Transaction
Ceded Credit Risk [Line Items]
Ceding Percentage	48.00%
Third-party Reinsurers \| Reinsurance Policy, Type [Axis]: 2023 QSR Transaction
Ceded Credit Risk [Line Items]
Ceding Percentage	20.00%
Third-party Reinsurers \| Reinsurance Policy, Type [Axis]: 2024 QSR Transaction
Ceded Credit Risk [Line Items]
Ceding Percentage	20.00%
Third-party Reinsurers \| Reinsurance Policy, Type [Axis]: 2025 QSR Transaction
Ceded Credit Risk [Line Items]
Ceding Percentage	20.00%
Third-party Reinsurers \| Reinsurance Policy, Type [Axis]: 2026 QSR Transactions
Ceded Credit Risk [Line Items]
Ceding Percentage	25.00%
Third-party Reinsurers \| Reinsurance Policy, Type [Axis]: 2027 QSR Transactions
Ceded Credit Risk [Line Items]
Ceding Percentage	35.00%
Third-party Reinsurers \| Reinsurance Policy, Type [Axis]: 2028 QSR Transactions
Ceded Credit Risk [Line Items]
Ceding Percentage	25.00%
Third-party Reinsurers \| Reinsurance Policy, Type [Axis]: Oaktown Re Vehicles
Ceded Credit Risk [Line Items]
Risk premiums paid	$ 2,400	$ 3,300
Third-party Reinsurers \| Reinsurance Policy, Type [Axis]: Oaktown Re Vehicles \| Maximum
Ceded Credit Risk [Line Items]
Anticipated payment related to annual operating expenses	$ 250

Reserves for Insurance Claims and Claim Expenses - Schedule of Reconciliation of Liability for Insurance Claims and Claim Expenses (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward]
Beginning balance	$ 196,429	$ 152,071
Less reinsurance recoverables	(38,577)	(32,260)
Beginning balance, net of reinsurance recoverables	157,852	119,811
Claims and claim expenses incurred:
Current year	47,150	34,559
Prior years	(26,489)	(30,081)
Total claims and claim expenses incurred	20,661	4,478
Claims and claim expenses paid:
Current year	0	0
Prior years	8,682	4,076
Reinsurance terminations	(1,670)	(255)
Total claims and claim expenses paid	7,012	3,821
Reserve at end of period, net of reinsurance recoverables	171,501	120,468
Add reinsurance recoverables	39,703	31,379
Ending balance	211,204	151,847
Current year case reserves	34,800	25,900
Current year IBNR	11,700	8,100
Prior year case reserves	15,200	(21,800)
Prior year, IBNR	$ 10,800	$ (8,100)

Organization, Basis of Presentation and Summary of Accounting Principles (Details)	Mar. 31, 2026 state
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of states in which the entity operates	50

Fair Value of Financial Instruments (Tables)

3 Months Ended

Mar. 31, 2026

Fair Value Disclosures [Abstract]

Schedule of Fair Value Measurements of Financial Instruments

The following tables present our financial instruments that are measured at fair value on a recurring basis by hierarchy level:


	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 March 31, 2026	(In Thousands)
U.S. Treasury securities and obligations of U.S. government agencies	$	257,184	$	—	$	—	$	257,184
Municipal debt securities	—		595,265		—		595,265
Corporate debt securities	—		2,161,747		—		2,161,747
U.S. agency mortgage-backed securities	—		40,576		—		40,576
Other asset-backed securities	—		93,951		—		93,951
Cash, cash equivalents and short-term investments	96,063		—		—		96,063
Total assets	$	353,247	$	2,891,539	$	—	$	3,244,786


	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, 2025	(In Thousands)
U.S. Treasury securities and obligations of U.S. government agencies	$	307,028	$	—	$	—	$	307,028
Municipal debt securities	—		611,569		—		611,569
Corporate debt securities	—		2,019,611		—		2,019,611
U.S. agency mortgage-backed securities	—		42,071		—		42,071
Other asset-backed securities	—		70,125		—		70,125
Cash, cash equivalents and short-term investments	130,556		—		—		130,556
Total assets	$	437,584	$	2,743,376	$	—	$	3,180,960

Debt (Details) - USD ($)			3 Months Ended
Debt (Details) - USD ($)	May 21, 2024	Apr. 29, 2024	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025
Revolving Credit Facility
Debt Instrument [Line Items]
Commitment fees in interest expense			$ 100,000	$ 100,000
Unsecured Debt \| On or After July 15, 2029
Debt Instrument [Line Items]
Redemption price (in percent)	100.00%
Senior 2024 Notes \| Unsecured Debt
Debt Instrument [Line Items]
Senior notes			425,000,000
Stated interest rate (in percent)	6.00%
Original issuance discount	$ 10,900,000		7,500,000
Effective interest rate (in percent)	6.583%
Senior 2024 Notes \| Secured Debt
Debt Instrument [Line Items]
Original issuance discount					$ 8,000,000.0
Interest payable			3,300,000		9,600,000
2024 Revolving Credit Facility \| Revolving Credit Facility
Debt Instrument [Line Items]
Debt instrument term (years)		5 years
Borrowings outstanding			0		0
2024 Revolving Credit Facility \| Revolving Credit Facility \| Minimum
Debt Instrument [Line Items]
Commitment fee (in percent)		0.175%
2024 Revolving Credit Facility \| Revolving Credit Facility \| Maximum
Debt Instrument [Line Items]
Commitment fee (in percent)		0.525%
2024 Revolving Credit Facility \| Revolving Credit Facility \| Base rate
Debt Instrument [Line Items]
Variable rate floor (in percent)		1.00%
2024 Revolving Credit Facility \| Revolving Credit Facility \| Base rate \| Minimum
Debt Instrument [Line Items]
Basis spread on variable rate (in percent)		0.375%
2024 Revolving Credit Facility \| Revolving Credit Facility \| Base rate \| Maximum
Debt Instrument [Line Items]
Basis spread on variable rate (in percent)		1.875%
2024 Revolving Credit Facility \| Revolving Credit Facility \| Secured Overnight Financing Rate (SOFR) \| Minimum
Debt Instrument [Line Items]
Basis spread on variable rate (in percent)		1.375%
2024 Revolving Credit Facility \| Revolving Credit Facility \| Secured Overnight Financing Rate (SOFR) \| Maximum
Debt Instrument [Line Items]
Basis spread on variable rate (in percent)		2.875%
2021 Revolving Credit Facility \| Revolving Credit Facility
Debt Instrument [Line Items]
Credit facility borrowing capacity		$ 250,000,000
Debt instrument term (years)		4 years
Deferred debt issuance costs		$ 600,000
Remaining deferred issuance costs, net of accumulated amortization			$ 1,700,000		$ 1,800,000
Maximum debt-to-total capitalization (in percent)			35.00%
Secured Revolving Credit Facility 2024 \| Revolving Credit Facility
Debt Instrument [Line Items]
Credit facility borrowing capacity		250,000,000
Commitment fee (in percent)			0.175%
Revolving Credit Facility 2024 \| Revolving Credit Facility
Debt Instrument [Line Items]
Debt issuance costs		$ 2,100,000

Stockholders' Equity (Details) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2026 USD ($) $ / shares shares
Equity [Abstract]
Repurchased shares (in shares) \| shares	0.7
Shares repurchased, average price per share (in dollars per share) \| $ / shares	$ 38.65
Remaining authorized repurchase amount \| $	$ 198.2

Income Taxes	3 Months Ended
Income Taxes	Mar. 31, 2026
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes We are a U.S. taxpayer and are subject to a statutory U.S. federal corporate income tax rate of 21%. Taxable income is reported on our consolidated U.S. federal and various state income tax returns, filed by NMIH on behalf of itself and its subsidiaries. Our effective tax rate on pre-tax income was 20.5% and 21.9% for the three months ended March 31, 2026 and 2025, respectively. Our provision for income taxes for interim reporting periods is established based on our estimated annual effective tax rate for a given year. Our effective tax rate may fluctuate between interim periods due to the impact of discrete items not included in our estimated annual effective tax rate, including the tax effects associated with the vesting of RSUs and exercise of options. Such items are treated on a discrete basis in the reporting period in which they occur. 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), and only 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. As a result, our interim provision for income taxes for the three months ended March 31, 2026 and 2025 primarily represents a change in our net deferred tax liability. As of March 31, 2026 and December 31, 2025, we held $400.3 million of tax and loss bonds in “Prepaid Federal Income Taxes” on our condensed consolidated balance sheets.

- Definition

The entire disclosure for income tax.

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+ Details

Reinsurance - Schedule of ILN Transactions and XOL Transactions (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Oct. 26, 2021	Apr. 27, 2021
Reinsurance Policy, Type [Axis]: 2021-1 ILN
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Percentage of population with production prior to period start date (in percent)	1.00%
Reinsurance Policy, Type [Axis]: 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	$ 71,735
Initial First Layer Retained Loss			$ 163,708
Current First Layer Retained Loss	$ 161,975
Reinsurance Policy, Type [Axis]: 2021-2 ILN
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Percentage of population with production prior to period start date (in percent)	2.00%
Reinsurance Policy, Type [Axis]: 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	$ 163,111
Initial First Layer Retained Loss		$ 146,229
Current First Layer Retained Loss	143,359
Reinsurance Policy, Type [Axis]: 2022-1 XOL Transaction
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Initial Reinsurance Coverage	289,741
Current Reinsurance Coverage	137,567
Initial First Layer Retained Loss	133,366
Current First Layer Retained Loss	128,264
Reinsurance Policy, Type [Axis]: 2022-2 XOL Transaction
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Initial Reinsurance Coverage	154,306
Current Reinsurance Coverage	109,595
Initial First Layer Retained Loss	78,906
Current First Layer Retained Loss	72,011
Reinsurance Policy, Type [Axis]: 2022-3 XOL Transaction
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Initial Reinsurance Coverage	96,779
Current Reinsurance Coverage	70,905
Initial First Layer Retained Loss	106,265
Current First Layer Retained Loss	100,303
Reinsurance Policy, Type [Axis]: 2023-1 XOL Transaction
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Initial Reinsurance Coverage	89,864
Current Reinsurance Coverage	59,249
Initial First Layer Retained Loss	146,513
Current First Layer Retained Loss	140,573
Reinsurance Policy, Type [Axis]: 2023-2 XOL Transaction
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Initial Reinsurance Coverage	100,777
Current Reinsurance Coverage	57,358
Initial First Layer Retained Loss	136,875
Current First Layer Retained Loss	134,382
Reinsurance Policy, Type [Axis]: 2024 XOL Transaction
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Initial Reinsurance Coverage	162,500
Current Reinsurance Coverage	143,357
Initial First Layer Retained Loss	312,172
Current First Layer Retained Loss	310,606
Reinsurance Policy, Type [Axis]: 2025 XOL Transaction
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Initial Reinsurance Coverage	283,849
Current Reinsurance Coverage	275,896
Initial First Layer Retained Loss	321,331
Current First Layer Retained Loss	321,331
Reinsurance Policy, Type [Axis]: 2026-1 XOL Transaction
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Initial Reinsurance Coverage	42,371
Current Reinsurance Coverage	42,371
Initial First Layer Retained Loss	76,881
Current First Layer Retained Loss	$ 76,881

Regulatory Information - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2026	Dec. 31, 2025
NMIC and Re One combined
Statutory Accounting Practices [Line Items]
Net income amount	$ 32,800	$ 36,800
Statutory capital	3,371,435			$ 3,255,546
NMIC and Re One combined \| Forecast
Statutory Accounting Practices [Line Items]
Aggregate dividend capacity			$ 101,000
Re One
Statutory Accounting Practices [Line Items]
Statutory capital	$ 2,100			$ 2,100

Segment Reporting	3 Months Ended
Segment Reporting	Mar. 31, 2026
Segment Reporting [Abstract]
Segment Reporting	Segment Reporting We manage our business activities on a consolidated basis under a single reportable operating segment and our Chief Executive Officer (CEO) serves as our Chief Operating Decision Maker (CODM). Our Mortgage Insurance segment provides private mortgage insurance and ancillary loan review services, and our CODM evaluates our performance and allocates resources based on our consolidated financial results, including consolidated revenue, expenses, net income, assets and shareholders' equity. Our CODM reviews consolidated net income to assess segment profit and loss, and also evaluates the broader set of metrics to gauge our financial performance and make strategic decisions, such as whether to reinvest profits in our Mortgage Insurance segment or return capital to shareholders. The significant revenue and expense categories that are regularly reviewed by our CODM align with those presented on our condensed consolidated statements of operations and comprehensive income, and segment assets align with total assets as presented on our condensed consolidated balance sheets. The accounting policies governing our Mortgage Insurance segment are the same as those described in Item 8, “Financial Statements and Supplementary Data - Notes to Consolidated Financial Statements - Note 2 - Summary of Accounting Principles” of our 2025 10-K. Investment income, also referred to as interest revenue, is reported within “Net Investment Income” on our condensed consolidated statements of operations and was $29.0 million and $24.0 million for the three months ended March 31, 2026 and 2025, respectively. Amortization and depreciation expense for software, equipment, and leasehold improvements was $2.5 million and $2.9 million for the three months ended March 31, 2026 and 2025, respectively.

- Definition

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.

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+ Details

Cover - shares	3 Months Ended
Cover - shares	Mar. 31, 2026	Apr. 27, 2026
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2026
Document Transition Report	false
Entity File Number	001-36174
Entity Registrant Name	NMI Holdings, Inc.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	45-4914248
Entity Address, Address Line One	2100 Powell Street
Entity Address, City or Town	Emeryville
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	94608
City Area Code	855
Local Phone Number	530-6642
Title of 12(b) Security	Common Stock, par value $0.01
Trading Symbol	NMIH
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding (in shares)		75,971,891
Entity Central Index Key	0001547903
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2026
Document Fiscal Period Focus	Q1
Amendment Flag	false

Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended
Income Taxes (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025
Income Tax Disclosure [Abstract]
Effective income tax rate on pre-tax income or loss (in percent)	20.50%	21.90%
Prepaid federal income taxes	$ 400,258		$ 400,258

Premiums Receivable, Net	3 Months Ended
Premiums Receivable, Net	Mar. 31, 2026
Insurance [Abstract]
Premiums Receivable, Net	Premiums Receivable, Net 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. 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 established a $1.4 million reserve for premium write-offs at both March 31, 2026 and December 31, 2025. We separately 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 receivable was deemed immaterial at March 31, 2026 and December 31, 2025.

Premiums Receivable, Net (Details) - USD ($) $ in Millions	3 Months Ended
Premiums Receivable, Net (Details) - USD ($) $ in Millions	Mar. 31, 2026	Mar. 31, 2025
Insurance [Abstract]
Premium receivable, number of days to be written off	120 days
Premium receivable, allowance for credit loss, uncollected	$ 1.4	$ 1.4

Investments (Tables)

3 Months Ended

Mar. 31, 2026

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 March 31, 2026	(In Thousands)
U.S. Treasury securities and obligations of U.S. government agencies	$	259,668	$	1,328	$	(3,812)	$	257,184
Municipal debt securities	621,318		1,603		(27,656)		595,265
Corporate debt securities	2,210,982		13,083		(62,318)		2,161,747
U.S. agency mortgage-backed securities (1)	40,925		—		(349)		40,576
Other asset-backed securities	96,926		39		(3,014)		93,951
Total bonds	3,229,819		16,053		(97,149)		3,148,723
Short-term investments	25,384		—		*		25,384
Total investments	$	3,255,203	$	16,053	$	(97,149)	$	3,174,107


	Amortized Cost		Gross Unrealized				Fair Value
			Gains		Losses
As of December 31, 2025	(In Thousands)
U.S. Treasury securities and obligations of U.S. government agencies	$	306,168	$	2,544	$	(1,684)	$	307,028
Municipal debt securities	635,396		3,052		(26,879)		611,569
Corporate debt securities	2,047,122		27,504		(55,015)		2,019,611
U.S. agency mortgage-backed securities (1)	42,109		10		(48)		42,071
Other asset-backed securities	72,774		—		(2,649)		70,125
Total bonds	3,103,569		33,110		(86,275)		3,050,404
Short-term investments	86,605		15		(1)		86,619
Total investments	$	3,190,174	$	33,125	$	(86,276)	$	3,137,023

(1) 100% of our U.S. agency mortgage-backed securities at March 31, 2026 and December 31, 2025 are guaranteed by Ginnie Mae which has the full faith and credit of the U.S. federal government.

* Amounts not identifiable due to rounding.

Schedule of Corporate Debt Securities by Industry Group

The following table presents a breakdown of the fair value of our corporate debt securities by issuer industry group as of March 31, 2026 and December 31, 2025:


	March 31, 2026		December 31, 2025
Financial	41	%	39	%
Consumer	27		28
Utilities	10		11
Industrial	9		9
Technology	6		6
Communications	5		6
Basic Materials	2		1
Total	100	%	100	%

Schedule of Investments by Maturity


As of March 31, 2026	Amortized Cost		Fair Value
	(In Thousands)
Due in one year or less	$	266,378	$	264,645
Due after one through five years	1,672,647		1,619,527
Due after five through ten years	1,110,252		1,088,729
Due after ten years	68,075		66,679
U.S. agency mortgage-backed securities	40,925		40,576
Other asset-backed securities	96,926		93,951
Total investments	$	3,255,203	$	3,174,107


As of December 31, 2025	Amortized Cost		Fair Value
	(In Thousands)
Due in one year or less	$	292,846	$	292,232
Due after one through five years	1,713,613		1,672,123
Due after five through ten years	1,062,039		1,053,628
Due after ten years	6,793		6,844
U.S. agency mortgage-backed securities	42,109		42,071
Other asset-backed securities	72,774		70,125
Total investments	$	3,190,174	$	3,137,023

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 March 31, 2026		($ In Thousands)
U.S. Treasury securities and obligations of U.S. government agencies	18	$	194,270	$	(3,804)	1	$	534	$	(8)	19	$	194,804	$	(3,812)
Municipal debt securities	2	9,386		(6)		211	462,436		(27,650)		213	471,822		(27,656)
Corporate debt securities	82	470,222		(5,391)		148	756,507		(56,927)		230	1,226,729		(62,318)
U.S. agency mortgage-backed securities	3	40,576		(349)		—	—		—		3	40,576		(349)
Other asset-backed securities	12	65,553		(272)		15	22,393		(2,742)		27	87,946		(3,014)
Short-term investments	1	24,998		*		—	—		—		1	24,998		*
Total	118	$	805,005	$	(9,822)	375	$	1,241,870	$	(87,327)	493	$	2,046,875	$	(97,149)


	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, 2025		($ In Thousands)
U.S. Treasury securities and obligations of U.S. government agencies	11	$	204,062	$	(1,673)	5	$	1,993	$	(11)	16	$	206,055	$	(1,684)
Municipal debt securities	—	—		—		215	477,095		(26,879)		215	477,095		(26,879)
Corporate debt securities	13	43,546		(209)		159	836,050		(54,806)		172	879,596		(55,015)
U.S. agency mortgage-backed securities	2	27,109		(48)		—	—		—		2	27,109		(48)
Other asset-backed securities	7	33,836		(53)		16	36,289		(2,596)		23	70,125		(2,649)
Short-term investments	1	24,778		(1)		—	—		—		1	24,778		(1)
Total	34	$	333,331	$	(1,984)	395	$	1,351,427	$	(84,292)	429	$	1,684,758	$	(86,276)

* Amounts not identifiable due to rounding.

Schedule of Net Investment Income

The following table presents the components of net investment income:


	For the three months ended March 31,
		2026		2025
		(In Thousands)
Investment income (1)		$	28,953	$	24,035
Investment expenses		(349)		(349)
Net investment income		$	28,604	$	23,686

(1) Includes interest income recognized on cash and cash equivalents of $0.9 million during both the three months ended March 31, 2026 and 2025.

Schedule of Net Realized Investment Gains (Losses)

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


	For the three months ended March 31,
		2026		2025
		(In Thousands)
Gross realized investment gains		$	1,046	$	24
Gross realized investment losses		(1,193)		—
Net realized investment (losses) gains		$	(147)	$	24

- Definition

Tabular disclosure of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-9

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (aa)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 7: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (aaa)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 8: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 9: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

Reference 10: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

Reference 11: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

Reference 12: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

+ Details

Reinsurance - Schedule of the Inception Date, Covered Production Period, Contractual and Optional Termination Dates, Current Cession Rate, Ceding Commission and Profit Commission for Each Outstanding QSR Transaction (Details) - Third-party Reinsurers	3 Months Ended
	Mar. 31, 2026
Reinsurance Policy, Type [Axis]: 2018 QSR Transaction
Ceded Credit Risk [Line Items]
Ceding Commission	42.00%
Profit Commission	0.45
Reinsurance Policy, Type [Axis]: 2018 QSR Transaction, Period 1
Ceded Credit Risk [Line Items]
Ceding percentage	16.00%
Reinsurance Policy, Type [Axis]: 2018 QSR Transaction, Period 2
Ceded Credit Risk [Line Items]
Ceding percentage	13.00%
Reinsurance Policy, Type [Axis]: 2020 QSR Transaction
Ceded Credit Risk [Line Items]
Ceding percentage	21.00%
Ceding Commission	45.00%
Profit Commission	0.45
Reinsurance Policy, Type [Axis]: 2021 QSR Transaction
Ceded Credit Risk [Line Items]
Ceding percentage	20.00%
Ceding Commission	35.00%
Profit Commission	0.54
Reinsurance Policy, Type [Axis]: 2022 QSR Transaction
Ceded Credit Risk [Line Items]
Ceding percentage	20.00%
Ceding Commission	20.00%
Profit Commission	0.68
Reinsurance Policy, Type [Axis]: 2022 Seasoned QSR Transaction
Ceded Credit Risk [Line Items]
Ceding percentage	48.00%
Ceding Commission	53.00%
Profit Commission	0.38
Reinsurance Policy, Type [Axis]: 2023 QSR Transaction
Ceded Credit Risk [Line Items]
Ceding percentage	20.00%
Ceding Commission	20.00%
Profit Commission	0.63
Reinsurance Policy, Type [Axis]: 2024 QSR Transaction
Ceded Credit Risk [Line Items]
Ceding percentage	20.00%
Ceding Commission	20.00%
Profit Commission	0.56
Reinsurance Policy, Type [Axis]: 2025 QSR Transaction
Ceded Credit Risk [Line Items]
Ceding percentage	20.00%
Ceding Commission	20.00%
Profit Commission	0.62
Reinsurance Policy, Type [Axis]: 2026 QSR Transactions
Ceded Credit Risk [Line Items]
Ceding percentage	25.00%
Ceding Commission	21.00%
Profit Commission	0.61
Reinsurance Policy, Type [Axis]: 2027 QSR Transactions
Ceded Credit Risk [Line Items]
Ceding percentage	35.00%
Reinsurance Policy, Type [Axis]: 2028 QSR Transactions
Ceded Credit Risk [Line Items]
Ceding percentage	25.00%

Reserves for Insurance Claims and Claim Expenses - Narrative (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2026 USD ($) claim loan policy	Mar. 31, 2025 USD ($)	Dec. 31, 2025 USD ($) loan policy	Dec. 31, 2024 USD ($)
Liability for Claims and Claims Adjustment Expense [Line Items]
Total gross liability for unpaid claims and claim adjustment expenses	$ 211,204	$ 151,847	$ 196,429	$ 152,071
Number of claims paid \| claim	170
Claims paid, including amounts covered by insurance	$ 10,800
Primary loans in default \| loan	8,044		7,661
Primary insured portfolio, loan default rate (in percent)	1.17%		1.12%
Total number of policies in-force \| policy	684,977		684,058
Favorable development on prior year defaults	$ 26,500	$ 30,100
Reserve for prior year insurance claims and claim expenses	$ 153,000
Reinsurance Policy, Type [Axis]: QSR Transactions
Liability for Claims and Claims Adjustment Expense [Line Items]
Number of covered claims included in number of claims paid \| claim \| claim	164
Component of claims paid covered under QSR Transaction	$ 2,100

Regulatory Information

3 Months Ended

Mar. 31, 2026

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.

NMIC and Re One generated combined statutory net income of $32.8 million and $36.8 million for the three months ended March 31, 2026 and 2025, respectively.

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 NMIC's statutory capital position.

The following table presents NMIC's statutory surplus, contingency reserve, statutory capital and risk-to-capital (RTC) ratio as of March 31, 2026 and December 31, 2025.



	March 31, 2026		December 31, 2025
	(In Thousands)
Statutory surplus	$	1,042,766	$	1,010,274
Contingency reserve	2,328,669		2,245,272
Statutory capital (1)	$	3,371,435	$	3,255,546

Risk-to-capital	13.3:1		13.0:1

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

Re One had $2.1 million of statutory capital at both March 31, 2026 and December 31, 2025.

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 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. NMIC has the capacity to pay $101.0 million of aggregate ordinary dividends to NMIH during the twelve-month period ending December 31, 2026.

- Definition

The entire disclosure for the types of coverages and products sold, and the assets, obligations, recorded liabilities, revenues and expenses arising therefrom, and the amounts of and methodologies and assumptions used in determining the amounts of such items.

+ References + Details

Investments - Schedule of Corporate Debt Securities by Industry Group (Details)	Mar. 31, 2026	Dec. 31, 2025
Debt Securities, Available-for-sale [Line Items]
Corporate debt securities as component of total (in percent)	100.00%	100.00%
Financial
Debt Securities, Available-for-sale [Line Items]
Corporate debt securities as component of total (in percent)	41.00%	39.00%
Consumer
Debt Securities, Available-for-sale [Line Items]
Corporate debt securities as component of total (in percent)	27.00%	28.00%
Utilities
Debt Securities, Available-for-sale [Line Items]
Corporate debt securities as component of total (in percent)	10.00%	11.00%
Industrial
Debt Securities, Available-for-sale [Line Items]
Corporate debt securities as component of total (in percent)	9.00%	9.00%
Technology
Debt Securities, Available-for-sale [Line Items]
Corporate debt securities as component of total (in percent)	6.00%	6.00%
Communications
Debt Securities, Available-for-sale [Line Items]
Corporate debt securities as component of total (in percent)	5.00%	6.00%
Basic Materials
Debt Securities, Available-for-sale [Line Items]
Corporate debt securities as component of total (in percent)	2.00%	1.00%

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

+ Details

Debt	3 Months Ended
Debt	Mar. 31, 2026
Debt Disclosure [Abstract]
Debt	Debt Senior Unsecured Notes At March 31, 2026, we had $425 million aggregate principal amount of senior unsecured notes outstanding. The 2024 Notes were issued pursuant to an indenture, dated May 21, 2024, and bear interest at a rate of 6.00%, payable semi-annually on February 15 and August 15. The 2024 Notes mature on August 15, 2029. We may elect to redeem the 2024 Notes in whole or in part at any time prior to July 15, 2029 at a price equal to the greater of (1) the aggregate principal balance outstanding plus the present value of all future interest payments due through July 15, 2029, and (2) the aggregate principal balance due plus any accrued and unpaid interest. We may elect to redeem the 2024 Notes in whole or in part at any time on or after July 15, 2029 at a price equal to 100% of the aggregate principal amount of the 2024 Notes to be redeemed plus accrued and unpaid interest thereon. In connection with the 2024 Notes offering, we recorded capitalized debt issuance costs and an original issue discount of $10.9 million. Such amount will be amortized over the contractual life of the 2024 Notes using the effective interest method and included in interest expense. The effective interest rate on the 2024 Notes is 6.583%. At March 31, 2026 and December 31, 2025, $7.5 million and $8.0 million, respectively, of unamortized debt issuance costs and original issue discount remained. At March 31, 2026 and December 31, 2025, $3.3 million and $9.6 million, respectively, of accrued and unpaid interest on the 2024 Notes was included in “Accounts Payable and Accrued Expenses” on our condensed consolidated balance sheets. Revolving Credit Facility On April 29, 2024, we entered into a new $250 million five-year unsecured revolving credit facility (the 2024 Revolving Credit Facility) to replace our then outstanding $250 million four-year secured revolving credit facility (the 2021 Revolving Credit Facility). The 2024 Revolving Credit Facility matures on May 21, 2029. Borrowings under the 2024 Revolving Credit Facility may be used for general corporate purposes, including to support growth, 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 2024 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 Secured Overnight Financing Rate (SOFR, as defined in the 2024 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 March 31, 2026 and December 31, 2025, no amounts were drawn under the 2024 Revolving Credit Facility. Under the 2024 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 March 31, 2026, the applicable commitment fee was 0.175%. For the three months ended March 31, 2026 and 2025, we recorded $0.1 million of commitment fees in interest expense. We incurred debt issuance costs of $2.1 million in connection with the 2024 Revolving Credit Facility and had $0.6 million of unamortized debt issuance costs associated with the 2021 Revolving Credit Facility remaining at the time of its replacement. Combined unamortized debt issuance costs are amortized through interest expense on a straight-line basis over the contractual life of the 2024 Revolving Credit Facility. At March 31, 2026 and December 31, 2025, remaining unamortized deferred debt issuance costs of $1.7 million and $1.8 million, respectively, were recorded in “Other Assets” on our condensed consolidated balance sheets. Under the 2024 Revolving Credit Facility we are subject to certain covenants, including a maximum debt-to-total capitalization ratio of 35%, a minimum consolidated net worth requirement (as defined therein), and a requirement to maintain compliance with the financial standards prescribed by the private mortgage insurer eligibility requirements (PMIERs). We were in compliance with all covenants at March 31, 2026.

- 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://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 8A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-8A

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
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-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
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Reference 10: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org/470/tableOfContent

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
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Reference 14: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Regulatory Information - Schedule of Statutory Net Income (loss), Surplus, Contingency Reserve and Risk-to-Capital Ratio (Details) - NMIC and Re One combined $ in Thousands	Mar. 31, 2026 USD ($)	Dec. 31, 2025 USD ($)
Statutory Accounting Practices [Line Items]
Statutory surplus	$ 1,042,766	$ 1,010,274
Contingency reserve	2,328,669	2,245,272
Statutory capital	$ 3,371,435	$ 3,255,546
Risk-to-capital	13.3	13.0

CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Assets
Fixed maturities, available-for-sale, at fair value (amortized cost of $3,255,203 and $3,190,174)	$ 3,174,107	$ 3,137,023
Cash and cash equivalents	70,679	43,937
Premiums receivable, net	86,861	86,259
Accrued investment income	29,726	27,253
Deferred policy acquisition costs, net	64,330	64,372
Software and equipment, net	20,887	21,727
Intangible assets and goodwill	3,634	3,634
Reinsurance recoverable	39,703	38,577
Prepaid federal income taxes	400,258	400,258
Other assets	19,453	18,058
Total assets	3,909,638	3,841,098
Liabilities
Debt	417,522	417,031
Unearned premiums	43,680	46,660
Accounts payable and accrued expenses	104,835	101,595
Reserve for insurance claims and claim expenses	211,204	196,429
Deferred tax liability, net	491,879	478,890
Other liabilities	8,086	8,507
Total liabilities	1,277,206	1,249,112
Commitments and contingencies
Shareholders' equity
Common stock - $0.01 par value; 88,951,544 shares issued and 76,149,574 shares outstanding as of March 31, 2026 and 88,371,465 shares issued and 76,285,242 shares outstanding as of December 31, 2025 (250,000,000 shares authorized)	890	884
Additional paid-in capital	1,007,682	1,016,772
Treasury stock, at cost: 12,801,970 and 12,086,223 common shares as of March 31, 2026 and December 31, 2025, respectively	(379,495)	(351,772)
Accumulated other comprehensive loss, net of tax	(68,160)	(46,083)
Retained earnings	2,071,515	1,972,185
Total shareholders' equity	2,632,432	2,591,986
Total liabilities and shareholders' equity	$ 3,909,638	$ 3,841,098

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME (UNAUDITED) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Revenues
Net premiums earned	$ 154,806	$ 149,366
Net investment income	28,604	23,686
Net realized investment (losses) gains	(147)	24
Other revenues	212	170
Total revenues	183,475	173,246
Expenses
Insurance claims and claim expenses	20,661	4,478
Underwriting and operating expenses	30,623	30,175
Service expenses	139	116
Interest expense	7,109	7,106
Total expenses	58,532	41,875
Income before income taxes	124,943	131,371
Income tax expense	25,613	28,812
Net income	$ 99,330	$ 102,559
Earnings per share
Basic (in dollars per share)	$ 1.30	$ 1.31
Diluted (in dollars per share)	$ 1.28	$ 1.28
Weighted average common shares outstanding
Basic (in shares)	76,175	78,407
Diluted (in shares)	77,435	79,858
Comprehensive income:
Net income	$ 99,330	$ 102,559
Other comprehensive (loss) income, net of tax:
Unrealized (losses) gains in accumulated other comprehensive loss, net of tax (benefit) expense of $(5,959) and $8,186 for the quarters ended March 31, 2026 and 2025, respectively	(22,415)	30,795
Reclassification adjustment for realized losses (gains) included in net income, net of tax (benefit) expense of $(90) and $5 for the quarters ended March 31, 2026 and 2025, respectively	338	(19)
Other comprehensive (loss) income, net of tax	(22,077)	30,776
Comprehensive income	$ 77,253	$ 133,335

Earnings per Share (EPS)

3 Months Ended

Mar. 31, 2026

Earnings Per Share [Abstract]

Earnings per Share (EPS)

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.

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 three months ended March 31,
		2026		2025
		(In Thousands, except for per share data)
Net income – basic and diluted		$	99,330	$	102,559





Basic weighted average shares outstanding		76,175		78,407







Dilutive effect of issuable shares		1,260		1,451
Diluted weighted average shares outstanding		77,435		79,858

Earnings per share
Basic		$	1.30	$	1.31
Diluted		$	1.28	$	1.28



Anti-dilutive shares		6		—

Reinsurance

3 Months Ended

Mar. 31, 2026

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).

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


	For the three months ended March 31,
		2026		2025
		(In Thousands)
Net premiums written
Direct		$	186,006	$	174,415
Ceded (1)		(34,180)		(31,029)
Net premiums written		$	151,826	$	143,386

Net premiums earned
Direct		$	188,986	$	180,456
Ceded (1)		(34,180)		(31,090)
Net premiums earned		$	154,806	$	149,366

(1) Net of profit commission.

Quota Share Reinsurance

NMIC is party to nine quota share reinsurance treaties – the 2018 QSR Transaction, effective January 1, 2018, the 2020 QSR Transaction, effective April 1, 2020, the 2021 QSR Transaction, effective January 1, 2021, the 2022 QSR Transaction, effective October 1, 2021, the 2022 Seasoned QSR Transaction, effective July 1, 2022, the 2023 QSR Transaction, effective January 1, 2023, the 2024 QSR Transaction, effective January 1, 2024, the 2025 QSR Transaction, effective January 1, 2025, and the 2026 QSR Transaction, effective January 1, 2026 – 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 to panels of third-party reinsurance providers in exchange for reimbursement of ceded claims and claim expenses on covered policies, a ceding commission and a profit commission (up to a contractually defined maximum) that varies directly and inversely with ceded claims.

NMIC holds optional termination rights which provide it with the discretion to terminate each QSR Transaction on or after a specified date. NMIC may also 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.

Each of the third-party reinsurance providers that is party to the QSR Transactions has an insurer financial strength rating of A- or better by S&P, A.M. Best or both.

Inception Date

Covered Production

Ceding Percentage

Ceding Commission

Profit Commission

2018 QSR

1/1/2018

1/1/2018 – 12/31/2018

1/1/2019 – 12/31/2019

16%

13% (1)

42%

up to 45%

2020 QSR

4/1/2020

4/1/2020 – 12/31/2020

21%

45%

up to 45%

2021 QSR

1/1/2021

1/1/2021 – 10/30/2021

20%

35%

up to 54%

2022 QSR

10/1/2021

10/30/2021 – 12/31/2022

20%

up to 68%

2022 Seasoned QSR

7/1/2022

1/1/2013 – 12/31/2016

7/1/2019 –3/31/2020

48% (2)

53%

up to 38%

2023 QSR

1/1/2023

1/1/2023 – 12/31/2023

20%

up to 63%

2024 QSR

1/1/2024

1/1/2024 – 12/31/2024

20%

up to 56%

2025 QSR

1/1/2025

1/1/2025 – 12/31/2025

20%

up to 62%

2026 QSR

1/1/2026

1/1/2026 – 12/31/2026

25%

21%

up to 61%

(1) Under the terms of the 2018 QSR Transaction, NMIC cedes premiums earned related to 16% of the risk on eligible policies written in 2018 and 13% of the risk on eligible policies written in 2019.

NMIC has also entered into two additional quota share reinsurance treaties that will provide sequential coverage for mortgage insurance policies to be written in 2027 and 2028 (the 2027 QSR Transaction and 2028 QSR Transaction). Under the terms of the 2027 QSR Transaction, NMIC will cede premiums earned related to 35% of the risk on eligible policies written between January 1, 2027 and December 31, 2027. Under the terms of the 2028 QSR Transaction, NMIC will cede premiums earned related to 25% of the risk on eligible policies written between January 1, 2028 and December 31, 2028.

The following table shows amounts related to the QSR Transactions:


	As of and for the three months ended
		March 31, 2026		March 31, 2025
		(In Thousands)
Ceded risk-in-force		$	12,189,562	$	12,888,870
Ceded premiums earned		(37,930)		(41,011)
Ceded claims and claim expenses		4,890		523
Ceding commission earned		10,205		9,768
Profit commission		17,131		23,398

NMIC had aggregate reinsurance recoverables related to the QSR Transactions of $39.7 million and $38.6 million as of March 31, 2026 and December 31, 2025, respectively. NMIC's reinsurance recoverable balance is supported by collateral trust accounts established and maintained by each reinsurer in accordance with the terms of the QSR Transactions and the PMIERs funding requirements for risk ceded to non-affiliated reinsurers.

We remain directly liable for all claim payments if we are unable to collect the recoverables due from our reinsurers and establish an allowance for expected credit loss against our reinsurance recoverable if we do not expect to recover amounts due from one or more of our reinsurance counterparties. Our reinsurance recoverable is reported 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 the QSR Transactions. The allowance for credit loss established against our reinsurance recoverable was deemed immaterial as of March 31, 2026 and December 31, 2025.

Excess-of-loss Reinsurance

Traditional Reinsurance

NMIC is party to eight excess-of-loss reinsurance agreements with broad panels of third-party reinsurers – the 2022-1 XOL Transaction, effective April 1, 2022, the 2022-2 XOL Transaction, effective July 1, 2022, the 2022-3 XOL Transaction, effective October 1, 2022, the 2023-1 XOL Transaction, effective January 1, 2023, the 2023-2 XOL Transaction, effective July 1,

2023, the 2024 XOL Transaction, effective January 1, 2024, the 2025 XOL Transaction, effective January 1, 2025, and the 2026-1 XOL Transaction, effective January 1, 2026 – which we refer to collectively as the XOL Transactions. Each XOL Transaction provides NMIC with aggregate excess-of-loss reinsurance coverage on a defined portfolio of mortgage insurance policies. Under each agreement, NMIC retains a first layer of aggregate loss exposure on covered policies and the reinsurers then provide second layer loss protection up to a defined reinsurance coverage amount. The reinsurance coverage amount of each XOL Transaction is set to approximate the PMIERs minimum required assets of its reference pool and decreases from its peak over a ten-year period in the event the PMIERs minimum required assets of the pool declines. NMIC retains losses in excess of the outstanding reinsurance coverage amount.

Under the terms of the XOL Transactions, NMIC makes risk premium payments to its third-party reinsurance providers for the outstanding reinsurance coverage amount and ceded aggregate premiums earned of $11.0 million and $10.2 million during the three months ended March 31, 2026 and 2025, respectively. NMIC applies claims paid on covered policies against its first layer aggregate retained loss exposure under each agreement. NMIC did not cede any incurred losses on covered policies under the XOL Transactions during the three months ended March 31, 2026 and 2025, as the aggregate first layer risk retention for each agreement was not exhausted during such periods.

NMIC holds optional termination rights which provide it with the discretion to terminate each XOL Transaction on or after a specified date. NMIC may also elect to terminate the XOL Transactions at any point if the outstanding reinsurance coverage amount amortizes to 10% or less of the reinsurance coverage amount provided at inception, or if it determines that it will no longer be able to take full PMIERs asset credit for the coverage. Additionally, under the terms of the treaties, NMIC may selectively terminate its engagement with individual reinsurers 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 obligation.

Each of the third-party reinsurance providers that is party to the XOL Transactions has an insurer financial strength rating of A- or better by S&P Global Ratings (S&P), A.M. Best Company Inc. (A.M. Best) or both.


($ values in thousands)	Inception Date	Covered Production	Initial Reinsurance Coverage		Current Reinsurance Coverage		Initial First Layer Retained Loss		Current First Layer Retained Loss (1)
2022-1 XOL	April 1, 2022	10/1/2021 – 3/31/2022	$	289,741	$	137,567	$	133,366	$	128,264
2022-2 XOL	July 1, 2022	4/1/2022 – 6/30/2022	154,306		109,595		78,906		72,011
2022-3 XOL	October 1, 2022	7/1/2022 – 9/30/2022	96,779		70,905		106,265		100,303
2023-1 XOL	January 1, 2023	10/1/2022 – 6/30/2023	89,864		59,249		146,513		140,573
2023-2 XOL	July 1, 2023	7/1/2023 – 12/31/2023	100,777		57,358		136,875		134,382
2024 XOL	January 1, 2024	1/1/2024 – 12/31/2024	162,500		143,357		312,172		310,606
2025 XOL	January 1, 2025	1/1/2025 – 12/31/2025	283,849		275,896		321,331		321,331
2026-1 XOL(2)	January 1, 2026	1/1/2026 – 12/31/2026	42,371		42,371		76,881		76,881

NMIC has also entered into two additional excess-of-loss reinsurance treaties that will incept and provide coverage in future periods. The 2026-2 XOL Transaction will incept on April 1, 2026 and provide $148 million of aggregate excess-of-loss coverage for mortgage insurance policies covered under the existing 2021-1 ILN Transaction, and the 2027 XOL Transaction will provide $125 million of aggregate excess-of-loss coverage for mortgage insurance policies to be written in 2027.

Insurance-Linked Notes

NMIC is a party to reinsurance agreements with Oaktown Re VI Ltd. and Oaktown Re VII Ltd. (special purpose reinsurance entities collectively referred to as the Oaktown Re Vehicles) effective April 27, 2021 and October 26, 2021,

respectively. Each agreement provides NMIC with aggregate excess-of-loss reinsurance coverage on a defined portfolio 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). NMIC ceded aggregate premiums to the Oaktown Re Vehicles of $2.4 million and $3.3 million during the three months ended March 31, 2026 and 2025, respectively.

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 three months ended March 31, 2026 and 2025, 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 12.5 years from the inception date of their associated reinsurance agreement. We refer to NMIC’s reinsurance agreements with and the insurance-linked note issuances by Oaktown Re Vehicles individually as the 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 12.5-year period as the underlying insured mortgages are amortized or repaid, and/or the mortgage insurance coverage is canceled. 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 distribution of collateral assets 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).

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.

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 outstanding ILN Transaction. Current amounts are presented as of March 31, 2026.


($ values in thousands)	Inception Date	Covered Production	Initial Reinsurance Coverage		Current Reinsurance Coverage		Initial First Layer Retained Loss		Current First Layer Retained Loss (1)





2021-1 ILN (4)	April 27, 2021	10/1/2020 – 3/31/2021 (2)	$	367,238	$	71,735	$	163,708	$	161,975
2021-2 ILN	October 26, 2021	4/1/2021 – 9/30/2021 (3)	363,596		163,111		146,229		143,359

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

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

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

Organization, Basis of Presentation and Summary of Accounting Principles (Policies)	3 Months Ended
	Mar. 31, 2026
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	Basis of Presentation The accompanying unaudited condensed consolidated financial statements, which include the results of NMIH and its wholly-owned subsidiaries, have been prepared in accordance with the instructions to Form 10-Q as prescribed by the SEC for interim reporting and include other information and disclosures required by accounting principles generally accepted in the U.S. (GAAP). Our accounts are maintained in U.S. dollars. These statements should be read in conjunction with our consolidated financial statements and notes thereto for the year ended December 31, 2025, included in our 2025 10-K. All intercompany transactions have been eliminated. The preparation of financial statements in accordance with GAAP requires management to make estimates and assumptions that affect reported amounts of assets and liabilities, and the disclosure of contingent assets and liabilities as of the balance sheet date, as well as reported amounts of income and expenses for the reporting period. Actual results could differ from those estimates. In the opinion of management, these unaudited condensed consolidated financial statements include all adjustments (including normal recurring adjustments) that are necessary to present a fair statement of financial position, results of operations and cash flows for the periods presented. The results of operations for the interim period may not be indicative of the results that may be expected for the full year ending December 31, 2026.
Recent Accounting Pronouncements - Not Yet Adopted	Recent Accounting Pronouncements – Not Yet Adopted In November 2024, the FASB issued ASU 2024-03, Disaggregation of Income Statement Expense (Topic 220). The update expands disclosure requirements related to certain income statement expenses, including a requirement to provide a tabular disaggregation of certain operating expenses by category. The standard will take effect for all public business entities for annual reporting periods beginning after December 15, 2026, and interim reporting periods beginning after December 15, 2027. Early adoption is permitted. We are currently evaluating the impact the adoption of this ASU will have, if any, on our consolidated financial statements. In September 2025, the FASB issued ASU 2025-06, Targeted Accounting for Internal-Use Software (Topic 350). The update clarifies the criteria surrounding the capitalization of certain costs and expands related disclosure requirements. The standard will take effect for all public business entities for annual reporting periods beginning after December 15, 2027, and interim reporting periods within those annual reporting periods. Early adoption is permitted. We are currently evaluating the impact the adoption of this ASU will have, if any, on our consolidated financial statements.
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.
Earnings per Share (EPS)	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.
Premiums Receivable, Net	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. 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 established a $1.4 million reserve for premium write-offs at both March 31, 2026 and December 31, 2025. We separately 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 receivable was deemed immaterial at March 31, 2026 and December 31, 2025.

Fair Value of Financial Instruments - Narrative (Details) - Senior 2024 Notes - USD ($)	Mar. 31, 2026	Dec. 31, 2025	May 21, 2024
Unsecured Debt
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt instrument face amount			$ 425,000,000
Carried cost	$ 417,500,000
Unamortized debt issuance costs and original issuance discount	7,500,000		$ 10,900,000
Unsecured Debt \| Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of long term debt	$ 436,200,000
Secured Debt
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Carried cost		$ 417,000,000.0
Unamortized debt issuance costs and original issuance discount		8,000,000.0
Secured Debt \| Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of long term debt		$ 441,300,000

- Definition

Amount of unamortized debt discount (premium) and debt issuance costs.

+ References + Details

- Definition

Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

+ References

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Reference 8: http://www.xbrl.org/2003/role/exampleRef
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+ Details

- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

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-Topic 820
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Reference 10: http://www.xbrl.org/2009/role/commonPracticeRef
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+ Details

Investments - Schedule of Aging of Unrealized Losses (Details) $ in Thousands	Mar. 31, 2026 USD ($) security	Dec. 31, 2025 USD ($) security
Debt Securities, Available-for-sale [Line Items]
Number of securities, less than 12 months \| security	118	34
Fair value, less than 12 months	$ 805,005	$ 333,331
Unrealized losses, less than 12 months	$ (9,822)	$ (1,984)
Number of securities,12 months or greater \| security	375	395
Fair value, 12 months or greater	$ 1,241,870	$ 1,351,427
Unrealized loss position, 12 months or greater	$ (87,327)	$ (84,292)
Number of securities, total \| security	493	429
Fair Value	$ 2,046,875	$ 1,684,758
Unrealized Losses	$ (97,149)	$ (86,276)
U.S. Treasury securities and obligations of U.S. government agencies
Debt Securities, Available-for-sale [Line Items]
Number of securities, less than 12 months \| security	18	11
Fair value, less than 12 months	$ 194,270	$ 204,062
Unrealized losses, less than 12 months	$ (3,804)	$ (1,673)
Number of securities,12 months or greater \| security	1	5
Fair value, 12 months or greater	$ 534	$ 1,993
Unrealized loss position, 12 months or greater	$ (8)	$ (11)
Number of securities, total \| security	19	16
Fair Value	$ 194,804	$ 206,055
Unrealized Losses	$ (3,812)	$ (1,684)
Municipal debt securities
Debt Securities, Available-for-sale [Line Items]
Number of securities, less than 12 months \| security	2	0
Fair value, less than 12 months	$ 9,386	$ 0
Unrealized losses, less than 12 months	$ (6)	$ 0
Number of securities,12 months or greater \| security	211	215
Fair value, 12 months or greater	$ 462,436	$ 477,095
Unrealized loss position, 12 months or greater	$ (27,650)	$ (26,879)
Number of securities, total \| security	213	215
Fair Value	$ 471,822	$ 477,095
Unrealized Losses	$ (27,656)	$ (26,879)
Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Number of securities, less than 12 months \| security	82	13
Fair value, less than 12 months	$ 470,222	$ 43,546
Unrealized losses, less than 12 months	$ (5,391)	$ (209)
Number of securities,12 months or greater \| security	148	159
Fair value, 12 months or greater	$ 756,507	$ 836,050
Unrealized loss position, 12 months or greater	$ (56,927)	$ (54,806)
Number of securities, total \| security	230	172
Fair Value	$ 1,226,729	$ 879,596
Unrealized Losses	$ (62,318)	$ (55,015)
U.S. agency mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
Number of securities, less than 12 months \| security	3	2
Fair value, less than 12 months	$ 40,576	$ 27,109
Unrealized losses, less than 12 months	$ (349)	$ (48)
Number of securities,12 months or greater \| security	0	0
Fair value, 12 months or greater	$ 0	$ 0
Unrealized loss position, 12 months or greater	$ 0	$ 0
Number of securities, total \| security	3	2
Fair Value	$ 40,576	$ 27,109
Unrealized Losses	$ (349)	$ (48)
Other asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Number of securities, less than 12 months \| security	12	7
Fair value, less than 12 months	$ 65,553	$ 33,836
Unrealized losses, less than 12 months	$ (272)	$ (53)
Number of securities,12 months or greater \| security	15	16
Fair value, 12 months or greater	$ 22,393	$ 36,289
Unrealized loss position, 12 months or greater	$ (2,742)	$ (2,596)
Number of securities, total \| security	27	23
Fair Value	$ 87,946	$ 70,125
Unrealized Losses	$ (3,014)	$ (2,649)
Short-term investments
Debt Securities, Available-for-sale [Line Items]
Number of securities, less than 12 months \| security	1	1
Fair value, less than 12 months	$ 24,998	$ 24,778
Unrealized losses, less than 12 months		$ (1)
Number of securities,12 months or greater \| security	0	0
Fair value, 12 months or greater	$ 0	$ 0
Unrealized loss position, 12 months or greater	$ 0	$ 0
Number of securities, total \| security	1	1
Fair Value	$ 24,998	$ 24,778
Unrealized Losses		$ (1)

Fair Value of Financial Instruments

3 Months Ended

Mar. 31, 2026

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.

The following tables present our financial instruments that are measured at fair value on a recurring basis by hierarchy level:


	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 March 31, 2026	(In Thousands)
U.S. Treasury securities and obligations of U.S. government agencies	$	257,184	$	—	$	—	$	257,184
Municipal debt securities	—		595,265		—		595,265
Corporate debt securities	—		2,161,747		—		2,161,747
U.S. agency mortgage-backed securities	—		40,576		—		40,576
Other asset-backed securities	—		93,951		—		93,951
Cash, cash equivalents and short-term investments	96,063		—		—		96,063
Total assets	$	353,247	$	2,891,539	$	—	$	3,244,786


	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, 2025	(In Thousands)
U.S. Treasury securities and obligations of U.S. government agencies	$	307,028	$	—	$	—	$	307,028
Municipal debt securities	—		611,569		—		611,569
Corporate debt securities	—		2,019,611		—		2,019,611
U.S. agency mortgage-backed securities	—		42,071		—		42,071
Other asset-backed securities	—		70,125		—		70,125
Cash, cash equivalents and short-term investments	130,556		—		—		130,556
Total assets	$	437,584	$	2,743,376	$	—	$	3,180,960

There were no transfers between Level 2 and Level 3 of the fair value hierarchy during the three months ended March 31, 2026 or the year ended December 31, 2025.

Financial Instruments Not Measured at Fair Value

On May 21, 2024, we issued $425 million aggregate principal amount of senior unsecured notes that mature on August 15, 2029 (the 2024 Notes). At March 31, 2026, the 2024 Notes were carried at an amortized cost of $417.5 million, net of unamortized debt issuance costs and an original issue discount totaling $7.5 million, and had a fair value of $436.2 million as assessed under our Level 2 hierarchy. At December 31, 2025, the 2024 Notes were carried at an amortized cost of $417.0 million, net of unamortized debt issuance costs and an original issue discount totaling $8.0 million, and had a fair value of $441.3 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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (bbb)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 107
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482078/820-10-55-107

Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Topic 820
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-Name Accounting Standards Codification
-Section 55
-Paragraph 100
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482078/820-10-55-100

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
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-Name Accounting Standards Codification
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-Paragraph 2
-Subparagraph (c)(3)
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-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
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-Name Accounting Standards Codification
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-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-6A

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2E

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Section 50
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
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-URI https://asc.fasb.org/1943274/2147482106/820-10-50-6A

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
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-Name Accounting Standards Codification
-Section 50
-Paragraph 6A
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-6A

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
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-Name Accounting Standards Codification
-Section 50
-Paragraph 6A
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-6A

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
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Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
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-Subparagraph (g)
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Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 940
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-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478119/940-820-50-1

+ Details

CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY (UNAUDITED) (Parenthetical) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Statement of Stockholders' Equity [Abstract]
Change in unrealized investment gains/losses, tax expense (benefit)	$ (5,869)	$ 8,181

CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY (UNAUDITED) - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Treasury Stock, At Cost	Accumulated Other Comprehensive Loss	Retained Earnings
Beginning balance (in shares) at Dec. 31, 2024		78,601,000
Beginning balance at Dec. 31, 2024	$ 2,217,432	$ 879	$ 1,004,692	$ (246,594)	$ (124,804)	$ 1,583,259
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock: shares issued under stock plans, net of shares withheld for employee taxes (in shares)		418,000
Common stock: shares issued under stock plans, net of shares withheld for employee taxes	(7,650)	$ 4	(7,654)
Repurchase of common stock (in shares)		(718,000)
Repurchase of common stock	(26,053)			(26,053)
Share-based compensation expense	4,507		4,507
Change in unrealized investment gains/losses, net of tax benefit (expense)	30,776				30,776
Net income	102,559					102,559
Ending balance (in shares) at Mar. 31, 2025		78,301,000
Ending balance at Mar. 31, 2025	$ 2,321,571	$ 883	1,001,545	(272,647)	(94,028)	1,685,818
Beginning balance (in shares) at Dec. 31, 2025	76,285,242	76,285,000
Beginning balance at Dec. 31, 2025	$ 2,591,986	$ 884	1,016,772	(351,772)	(46,083)	1,972,185
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock: shares issued under stock plans, net of shares withheld for employee taxes (in shares)		580,000
Common stock: shares issued under stock plans, net of shares withheld for employee taxes	(13,766)	$ 6	(13,772)
Repurchase of common stock (in shares)		(716,000)
Repurchase of common stock	(27,723)			(27,723)
Share-based compensation expense	4,682		4,682
Change in unrealized investment gains/losses, net of tax benefit (expense)	(22,077)				(22,077)
Net income	$ 99,330					99,330
Ending balance (in shares) at Mar. 31, 2026	76,149,574	76,149,000
Ending balance at Mar. 31, 2026	$ 2,632,432	$ 890	$ 1,007,682	$ (379,495)	$ (68,160)	$ 2,071,515

CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED) (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Statement of Financial Position [Abstract]
Debt securities, amortized cost	$ 3,255,203	$ 3,190,174
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, issued (in shares)	88,951,544	88,371,465
Common stock, outstanding (in shares)	76,149,574	76,285,242
Common stock, authorized (in shares)	250,000,000	250,000,000
Treasury stock, common shares (in shares)	12,801,970	12,086,223

Regulatory Information (Tables)

3 Months Ended

Mar. 31, 2026

Insurance [Abstract]

Schedule of Statutory Net Income (loss), Surplus, Contingency Reserve and Risk-to-Capital Ratio

The following table presents NMIC's statutory surplus, contingency reserve, statutory capital and risk-to-capital (RTC) ratio as of March 31, 2026 and December 31, 2025.



	March 31, 2026		December 31, 2025
	(In Thousands)
Statutory surplus	$	1,042,766	$	1,010,274
Contingency reserve	2,328,669		2,245,272
Statutory capital (1)	$	3,371,435	$	3,255,546

Risk-to-capital	13.3:1		13.0:1

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

- 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

Reserves for Insurance Claims and Claim Expenses (Tables)

3 Months Ended

Mar. 31, 2026

Insurance [Abstract]

Schedule of Reconciliation of Liability for Insurance Claims and Claim Expenses

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


	For the three months ended March 31,
	2026		2025
	(In Thousands)
Beginning balance	$	196,429	$	152,071
Less reinsurance recoverables (1)	(38,577)		(32,260)
Beginning balance, net of reinsurance recoverables	157,852		119,811

Add claims incurred:
Claims and claim expenses incurred:
Current year (2)	47,150		34,559
Prior years (3)	(26,489)		(30,081)
Total claims and claim expenses incurred	20,661		4,478

Less claims paid:
Claims and claim expenses paid:
Current year (2)	—		—
Prior years (3)	8,682		4,076
Reinsurance terminations (4)	(1,670)		(255)
Total claims and claim expenses paid	7,012		3,821

Reserve at end of period, net of reinsurance recoverables	171,501		120,468
Add reinsurance recoverables (1)	39,703		31,379
Ending balance	$	211,204	$	151,847

(1) Related to ceded losses recoverable under the QSR Transactions. See Note 5, “Reinsurance” for additional information.

(4) Represents the settlement of reinsurance recoverables in conjunction with the termination or amendment of certain QSR Transactions.

Stockholders' Equity	3 Months Ended
Stockholders' Equity	Mar. 31, 2026
Equity [Abstract]
Stockholders' Equity	Stockholders' EquityDuring the three months ended March 31, 2026, we repurchased 0.7 million shares at an average price of $38.65 per share (excluding associated costs and applicable taxes). As of March 31, 2026, we had $198.2 million of repurchase authorization remaining through December 31, 2027. The authorization provides us with the flexibility, based on market and business conditions, stock price and other factors, to repurchase stock through open market purchases, privately negotiated transactions, or other means, including pursuant to Rule 10b5-1 trading plans.

- Definition

The entire disclosure for equity.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 8A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-8A

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
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+ Details

Earnings per Share (EPS) (Tables)

3 Months Ended

Mar. 31, 2026

Earnings Per Share [Abstract]

Schedule of Earnings Per Share, Basic and Diluted

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 three months ended March 31,
		2026		2025
		(In Thousands, except for per share data)
Net income – basic and diluted		$	99,330	$	102,559





Basic weighted average shares outstanding		76,175		78,407







Dilutive effect of issuable shares		1,260		1,451
Diluted weighted average shares outstanding		77,435		79,858

Earnings per share
Basic		$	1.30	$	1.31
Diluted		$	1.28	$	1.28



Anti-dilutive shares		6		—

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME (UNAUDITED) (Parenthetical) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Income Statement [Abstract]
Unrealized gains (losses) in accumulated other comprehensive loss , net of tax (expense ) benefit	$ (5,959)	$ 8,186
Reclassification adjustment for realized losses (gains) included in net income, net of tax (benefit) expense	$ (90)	$ 5

Investments - Schedule of Investments by Maturity (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Amortized Cost
Due in one year or less	$ 266,378	$ 292,846
Due after one through five years	1,672,647	1,713,613
Due after five through ten years	1,110,252	1,062,039
Due after ten years	68,075	6,793
Amortized Cost	3,255,203	3,190,174
Fair Value
Due in one year or less	264,645	292,232
Due after one through five years	1,619,527	1,672,123
Due after five through ten years	1,088,729	1,053,628
Due after ten years	66,679	6,844
Fair Value	3,174,107	3,137,023
Other asset-backed securities
Amortized Cost
Other asset-backed securities	96,926	72,774
Fair Value
Other asset-backed securities	93,951	70,125
U.S. agency mortgage-backed securities
Amortized Cost
Other asset-backed securities	40,925	42,109
Amortized Cost	40,925	42,109
Fair Value
Other asset-backed securities	40,576	42,071
Fair Value	$ 40,576	$ 42,071

Insider Trading Arrangements	3 Months Ended
Insider Trading Arrangements	Mar. 31, 2026
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false