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Company Performance Measurement Input, Change in Guideline Public Company Multiples [Member] Measurement Input, Change in Guideline Public Company Multiples Terry Lee Ledbetter Terry Lee Ledbetter [Member] Terry Lee Ledbetter Share-based compensation arrangement by share-based payment award, equity instruments other than options, grants in period (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period Cancellation notice period Related Party Transaction, Cancellation Notice Period Related Party Transaction, Cancellation Notice Period Statement of Financial Position [Abstract] Statement of Financial Position [Abstract] Peer Group Total Shareholder Return Amount Peer Group Total Shareholder Return Amount Segment Concentration Risk Segment Concentration Risk [Member] Segment Concentration Risk [Member] Significant Other Observable Inputs (Level 2) Fair Value, Inputs, Level 2 [Member] Total Shareholder Return Vs Peer Group Total Shareholder Return Vs Peer Group [Text Block] Non-Rule 10b5-1 Arrangement Terminated Non-Rule 10b5-1 Arrangement Terminated [Flag] Kestrel Group Kestrel Group [Member] Kestrel Group Schedule of Composition of Other Investments Summary of Other Investments [Table Text Block] Summary of Other Investments [Table Text Block] Schedule of Reconciliation to Consolidated Total Assets Segment Reporting, Reconciliation of Asset by Segment to Consolidated [Table Text Block] UNITED STATES UNITED STATES Concentration Risk Type [Axis] Concentration Risk Type [Axis] Schedule of Long-term Debt Instruments [Table] Schedule of Long-Term Debt Instruments [Table] Other comprehensive (loss) income before reclassifications OCI, before Reclassifications, before Tax, Attributable to Parent Business combination, stock conversion ratio Business Combination, Stock Conversion Ratio Business Combination, Stock Conversion Ratio Percent of ceding commission payable, period increase Related Party Transaction, Percent Of Ceding Commission Payable, Period Increase (Decrease) Related Party Transaction, Percent Of Ceding Commission Payable, Period Increase (Decrease) Schedule of Reconciliation of Reportable Segments Underwriting Results to Consolidated Net Loss Segment Reporting [Table Text Block] Other comprehensive (loss) income Other Comprehensive Income (Loss), before Tax [Abstract] Related Party [Axis] Related and Nonrelated Parties [Axis] Reinsurance receivable Reinsurance Recoverables, Gross Other comprehensive (loss) income, after tax Net current period other comprehensive income (loss) Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent Accrued investment income Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Accrued investment income Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Accrued Investment Income AmTrust Financial Services, Inc. AmTrust Financial Services, Inc. AmTrust Financial Services, Inc. [Member] AmTrust Financial Services, Inc. [Member] Allowance for expected credit losses Debt Securities, Available-for-Sale, Allowance for Credit Loss, Writeoff Due after one year through five years Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year One Through Five Scheduled of Maturity of Operating Lease Liabilities Lessee, Operating Lease, Liability, to be Paid, Maturity [Table Text Block] Document Period End Date Document Period End Date Silverstone Venture 2 Silverstone Venture 2 [Member] Silverstone Venture 2 Debt instrument, principal amount Debt Instrument, Face Amount Reinsurance recoverables on unpaid losses Reinsurance Recoverables on Unpaid Losses, Gross 2028 Lessee, Operating Lease, Liability, to be Paid, Year Two Common Stock Held Indirectly Common Stock Ownership, Held Indirectly [Member] Common Stock Ownership, Held Indirectly Number of securities in an unrealized loss position Fixed Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of 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Schedule of Investments [Line Items] Schedule of Investments [Line Items] Investments in direct lending entities Direct Lending Entities [Member] Direct Lending Entities Investment, Name [Axis] Investment, Name [Axis] Fixed maturities Fixed Maturities [Member] Investments Investment Holdings [Text Block] Schedule of Effect of Ceded Reinsurance on Net Premiums Written and Earned and on Net Loss and LAE Effects of Reinsurance [Table Text Block] Fed funds rate Debt Instrument, Basis Spread on Variable Rate Other assets Business Combination, Recognized Asset Acquired, Other Asset, Current Restricted Stock Restricted Stock [Member] Accumulated other comprehensive (loss) income Total AOCI Attributable to Parent [Member] All Individuals All Individuals [Member] Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] Net equity 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reconciliation asset gain loss statement of other comprehensive income extensible list not disclosed flag Fair Value Recurring Basis Unobservable Input Reconciliation Asset Gain Loss Statement Of Other Comprehensive Income Extensible List Not Disclosed Flag Fair Value Recurring Basis Unobservable Input Reconciliation Asset Gain Loss Statement Of Other Comprehensive Income Extensible List Not Disclosed Flag Liabilities held for sale Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed, Liabilities Held For Sale Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed, Liabilities Held For Sale Adjustment to Compensation: Adjustment to Compensation [Axis] Investment Ownership, 5% Investment Ownership, 5 Percent [Member] Investment Ownership, 5 Percent Investment Ownership, 25% Investment Ownership, 25 Percent [Member] Investment Ownership, 25 Percent Rule 10b5-1 Arrangement Terminated Rule 10b5-1 Arrangement Terminated [Flag] 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Arrangements with AmTrust Schedule of Related Party Transactions [Table Text Block] Direct Direct Premiums Earned Post-Termination Endorsement, Maximum Loss Corridor Post-Termination Endorsement, Maximum Loss Corridor [Member] Post-Termination Endorsement, Maximum Loss Corridor [Member] 2030 Lessee, Operating Lease, Liability, to be Paid, Year Four Schedule of Investments [Abstract] Schedule of Investments [Abstract] Assets, valued by third party, percentage Assets, Fair Value Disclosure, Valued by Third Party, Percentage Assets, Fair Value Disclosure, Valued by Third Party, Percentage Investments: Investments [Abstract] Due after five years through ten years Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year 5 Through 10 Foreign exchange and other (gains) losses Foreign exchange and other (gains) losses Foreign exchange and other gains, net Foreign Currency Transaction and Other Gain (Loss), before Tax Foreign Currency Transaction 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AUM Financial Services, Inc. [Member] AUM Programs Financial Services, Inc. Weighted Average Amortization Period Weighted Average Amortization Period [Abstract] Weighted Average Amortization Period Organization, Consolidation and Presentation of Financial Statements [Abstract] Organization, Consolidation and Presentation of Financial Statements [Abstract] Exit Cap Rate Measurement Input, Cap Rate [Member] Schedule of Total Unfunded Commitments Other Commitments [Table Text Block] Kestrel Group, Ltd. Kestrel Group, Ltd. [Member] Kestrel Group, Ltd. 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[Member] Standard & Poor's, AA+, AA, AA- Rating Adoption Date Trading Arrangement Adoption Date Assets held for sale Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed, Assets Held For Sale Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed, Assets Held For Sale Counterparty Name [Domain] Counterparty Name [Domain] Equity securities: at fair value (Cost: 2026: $11,145; 2025: $11,145) Fair Value Equity securities Equity Securities, FV-NI, Current Title Trading Arrangement, Individual Title Forgone Recovery due to Disqualification of Tax Benefits, Amount Forgone Recovery due to Disqualification of Tax Benefits, Amount Direct Direct Premiums Written Accounting Policies [Abstract] Accounting Policies [Abstract] Restatement does not require Recovery Restatement Does Not Require Recovery [Text Block] Operating lease, liability Total discounted operating lease liabilities Operating Lease, Liability Insider Trading Policies 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Category: Executive Category [Axis] Accounting Treatment for the Combination Business Combination [Policy Text Block] Counterparty Name [Axis] Counterparty Name [Axis] Reinsurance Reinsurance [Text Block] Funds withheld receivable: (Allowance for expected credit losses: 2026: $2; 2025: $2) Funds withheld receivable Funds Held under Reinsurance Agreements, Asset Non-PEO NEO Average Compensation Actually Paid Amount Non-PEO NEO Average Compensation Actually Paid Amount Schedule of Variable Interest Entities [Table] Variable Interest Entity [Table] PEO Name PEO Name Net paid losses Liability for Unpaid Claims and Claims Adjustment Expense, Claims Paid Investee Revenue Equity Method Investments Investee Revenue Equity Method Investments Investee Revenue Accrued expenses and other liabilities (includes $25,163 and $16,443 from related parties in 2026 and 2025, respectively) Accrued expenses and other liabilities Accrued Liabilities and Other Liabilities Cash acquired from purchase of 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And Liabilities Assumed Accrued Expenses and Other Liabilities Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Accrued Expenses and Other Liabilities Reinsurance balances receivable, net Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Reinsurance Balances Receivable, Net Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Reinsurance Balances Receivable, Net Share-based compensation expense Share-Based Payment Arrangement, Noncash Expense Discount for Lack of Marketability - OPM Measurement​ Input ​Discount ​For ​Lack ​Of ​Marketability, OPM [Member] Measurement​ Input ​Discount ​For ​Lack ​Of ​Marketability, OPM Gross and net premiums written Premium Written Gross And Net Premium Written Gross And Net Schedule of Fixed Maturities in an Unrealized Loss Position and Aggregate Fair Value Securities, Continuous Unrealized Loss Position, Fair Value [Table Text Block] Securities, 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[Member] Silverstone Venture Premiums earned Premiums Earned, Net [Abstract] Schedule of Net Realized and Unrealized Investment Gains (Losses) Gain (Loss) on Securities [Table Text Block] Schedule of Stock by Class [Table] Stock, Class of Stock [Table] Kestrel Group Ltd share price (in dollars per share) Kestrel Group Ltd share price (in dollars per share) Business Combination, Price Per Share Underwriting-related derivative liability Derivative Liability Senior Notes Senior Notes [Member] Entity Address, Address Line One Entity Address, Address Line One Terry and Luke Ledbetter Terry and Luke Ledbetter [Member] Terry and Luke Ledbetter Loan Agreement Loan Agreement [Member] Loan Agreement Less: income tax (benefit) expense Income tax (benefit) expense Income tax benefit Income Tax Expense (Benefit) Collateralized loan obligations Collateralized Loan Obligations [Member] Deferred income tax Deferred Tax Assets, Deferred Income Cash and cash equivalents and investments Total restricted 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