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Reclassification adjustment for realized losses included in net income, net of tax benefit of $2 and $0 for the three months ended September 30, 2024 and 2023, and $2 and $7 for the nine months ended September 30, 2024 and 2023, respectively Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Net of Tax Due after five through ten years Debt Securities, Available-for-Sale, Maturity, Allocated and Single Maturity Date, Rolling after 5 through 10 Years, Amortized Cost Organization, Basis of Presentation and Summary of Accounting Principles Business Description and Basis of Presentation [Text Block] Number of quota share reinsurance treaties Number of Quota Share Reinsurance Treaties Number of Quota Share Reinsurance Treaties Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Total revenues Revenues On or After July 15, 2029 On or After July 15, 2029 [Member] On or After July 15, 2029 Other liabilities Other Liabilities Entity Address, City or Town Entity Address, City or Town 2025 XOL Transaction 2025 XOL Transaction [Member] 2025 XOL Transaction Debt Instrument [Axis] Debt Instrument [Axis] Net income Net income Net income Net Income (Loss) Attributable to Parent Investments, Debt and Equity Securities [Abstract] Investments, Debt and Equity Securities [Abstract] Net premiums written Premiums Written, Net Entity File Number Entity File Number Reserve for prior year insurance claims and claim expenses Liability for Prior Year Claims and Claims Adjustment Expense Liability for Prior Year Claims and Claims Adjustment Expense Cash and Cash Equivalents [Axis] Cash and Cash Equivalents [Axis] Schedule of Net Realized Investment Losses Realized Gain (Loss) on Investments [Table Text Block] Document Fiscal Year Focus Document Fiscal Year Focus Service expenses Other Nonoperating Expense Income Statement [Abstract] Income Statement [Abstract] Entity Address, Address Line One Entity Address, Address Line One Current Reinsurance Coverage Current Reinsurance Coverage Current Reinsurance Coverage Repurchase of common stock Treasury Stock, Value, Acquired, Cost Method Weighted average common shares outstanding Weighted Average Number of Shares Outstanding Reconciliation [Abstract] Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] Total assets Assets, Fair Value Disclosure Document Period End Date Document Period End Date Reinsurance retention policy excess of loss reinsurance coverages Reinsurance Retention Policy Excess Of Loss Reinsurance Coverages Reinsurance Retention Policy Excess Of Loss Reinsurance Coverages Base rate Base Rate [Member] Asset-backed securities Debt Securities, Available-for-Sale, Maturity, without Single Maturity Date, Fair Value Number of days to be written off Premium Receivable, Number of Days to be Written Off Premium Receivable, Number of Days to be Written Off Reinsurance balances, net Increase (Decrease) in Reinsurance Assets and Liabilities Increase (Decrease) in Reinsurance Assets and Liabilities Document Transition Report Document Transition Report Document Quarterly Report Document Quarterly Report Current year Current Year Claims and Claims Adjustment Expense Ceded claims and claim expenses Reinsurance Ceded Claims and Claims (Benefits) Expenses Reinsurance Ceded Claims and Claims (Benefits) Expenses Fair Value, Recurring and Nonrecurring [Table] Fair Value, Recurring and Nonrecurring [Table] Accumulated other comprehensive loss, net of tax Accumulated Other Comprehensive Income (Loss), Net of Tax Entity Current Reporting Status Entity Current Reporting Status Initial Reinsurance Coverage Initial Reinsurance Coverage Initial Reinsurance Coverage Financial Financial, Industry Group [Member] Financial, Industry Group [Member] Retained Earnings Retained Earnings [Member] Profit commission Reinsurance Profit Commission Reinsurance Profit Commission Basic (in shares) Basic weighted average shares outstanding (in shares) Weighted Average Number of Shares Outstanding, Basic Unrealized gains (losses) in accumulated other comprehensive loss , net of tax (expense ) benefit OCI, Debt Securities, Available-for-Sale, Unrealized Holding Gain (Loss), before Adjustment, Tax Net premiums earned Net premiums earned Premiums Earned, Net Unrealized loss position, 12 months or greater Unrealized loss position, 12 months or greater Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss Amortization of debt discount and debt issuance costs Amortization of Debt Issuance Costs and Discounts Net realized investment loss Net realized investment losses Debt Securities, Available-for-Sale, Realized Gain (Loss) Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Unrealized losses, less than 12 months Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss Entity Filer Category Entity Filer Category Purchase of fixed-maturity investments, available-for-sale Payments to Acquire Debt Securities, Available-for-Sale