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10b5-1 Arrangement Adopted [Flag] Schedule of Amortized Cost and Fair Value of Fixed Maturity Securities, Available-for-Sale Investments Classified by Contractual Maturity Date [Table Text Block] Equity securities Equity Securities [Member] Schedule of Unpaid Losses and Loss Adjustment Expenses, Net of Reinsurance Schedule of Liability for Unpaid Claims and Claims Adjustment Expense [Table Text Block] Weighted-Average Exercise Price Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract] Recovery of Erroneously Awarded Compensation Disclosure [Line Items] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration] Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration] 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Allocation Agreement [Member] Tax Allocation Agreement Product and Service [Domain] Product and Service [Domain] Related Party Related Party [Member] Cash paid (received) for taxes Income Tax Paid, after Refund Received Consulting Agreements Consulting Agreements [Member] Consulting Agreements Entity Interactive Data Current Entity Interactive Data Current Less: Net income (loss) attributable to non-controlling interest - General Partner Net Income (Loss) Attributable to Noncontrolling Interest Thereafter Lessee, Operating Lease, Liability, to be Paid, After Year Four Lessee, Operating Lease, Liability, to be Paid, After Year Four Variable Interest Entity [Line Items] Variable Interest Entity [Line Items] Compensation Actually Paid vs. Other Measure Compensation Actually Paid vs. Other Measure [Text Block] Shared services, renewal period Shared Services, Renewal Period Shared Services, Renewal Period Due after one year through five years Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, after Year One Through Five Expense associated with savings plans Defined Contribution Plan, Cost Entity Small Business Entity Small Business Total comprehensive income attributable to stockholders Comprehensive Income (Loss), Net of Tax, Attributable to Parent Unearned premiums Unearned Premiums Premium Receivable, Allowance for Credit Loss [Roll Forward] Premium Receivable, Allowance for Credit Loss [Roll Forward] 2029 Lessee, Operating Lease, Liability, to be Paid, Year Three Utility & Infrastructure Investments, cost Cost Alternative Investment, Cost Alternative Investment, Cost Termination Date Trading Arrangement Termination Date Property, Plant, and Equipment [Line Items] Property, Plant, and Equipment [Line Items] Effective Income Tax Rate Reconciliation [Table] Effective Income Tax Rate Reconciliation [Table] Subsequent Events [Abstract] Fair Value, Recurring and Nonrecurring [Table] Fair Value, Recurring and Nonrecurring [Table] Income tax expense at federal income tax rate Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent Compensation Actually Paid vs. Total Shareholder Return Compensation Actually Paid vs. Total Shareholder Return [Text Block] MidCap Limited Partnership MidCap Limited Partnership [Member] MidCap Limited Partnership Reverse stock split Stockholders' Equity Note, Stock Split, Conversion Ratio MNPI Disclosure Timed for Compensation Value MNPI Disclosure Timed for Compensation Value [Flag] Current year Current Year Claims and Claims Adjustment Expense Award term Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period Document Type Document Type 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] Fair Value as of Grant Date Award Grant Date Fair Value Schedule of Gross Unrealized Losses and Fair Value for Available-for-Sale Securities Aggregated by Investment Debt Securities, Available-for-Sale, Unrealized Loss Position, Fair Value [Table Text Block] Summary of Significant Accounting Policies Significant Accounting Policies [Text Block] Exercisable Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Intrinsic Value Pay vs Performance Disclosure, Table Pay vs Performance [Table Text Block] Remained available for future repurchases under the program Share Repurchase Program, Remaining Authorized, Amount Cash equivalents Cash and Cash Equivalents [Member] Arrangement Duration Trading Arrangement Duration Statement of Stockholders' Equity [Abstract] Local Phone Number Local Phone Number Consolidation Items [Axis] Consolidation Items [Axis] Entity Address, Postal Zip Code Entity Address, Postal Zip Code Registrant Name Entity Registrant Name Purchase of other assets Payments to Acquire Other Productive Assets Short-term investments Other Short-Term Investments Less than 12 months, Gross Unrealized (Losses) Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss Investment in securities, assets, cost Alternative Investments, Investment in Securities, Assets, Cost Alternative Investments, Investment in Securities, Assets, Cost Income before income taxes Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Reinsurance recoverable, net of allowance for credit losses Reinsurance Recoverable, Allowance for Credit Loss Insider Trading Policies and Procedures Not Adopted Insider Trading Policies and Procedures Not Adopted [Text Block] Exercise of warrants (in years) Warrants and Rights Outstanding, Term Total revenues Revenues Antidilutive Securities, Name [Domain] Antidilutive Securities, Name [Domain] Incentive allocation, percentage Incentive Allocation, Percentage Incentive Allocation, Percentage Changed Peer Group, Footnote Changed Peer Group, Footnote [Text Block] Treasury stock acquired - share repurchase program Payments For Repurchase Of Treasury Stock Payments For Repurchase Of Treasury Stock Utility & Infrastructure Investments, at fair value (cost of $182,753 in 2026 and $172,753 in 2025) Investments in the Absolute Return Utility & Infrastructure Fund, at fair value Fair Value Alternative Investment Forgone Recovery due to Expense of Enforcement, Amount Forgone Recovery due to Expense of Enforcement, Amount Executive Category: Executive Category [Axis] Schedule of Nonvested Restricted Stock Units Activity Schedule of Nonvested Restricted Stock Units Activity [Table Text Block] Award vesting period Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period Expired (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Expirations in Period Counterparty Name [Axis] Counterparty Name [Axis] Liabilities, stockholders' equity and non-controlling interest: Liabilities and Equity [Abstract] Reinsurance Reinsurance [Text Block] Exercisable (years) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Weighted-Average Remaining Contractual Term Movement Analysis of Deferred Policy Acquisition Costs [Roll Forward] Movement Analysis of Deferred Policy Acquisition Costs [Roll Forward] Net write-offs Premium Receivable, Allowance for Credit Loss, Writeoff, after Recovery Premium Receivable, Allowance for Credit Loss, Writeoff, after Recovery All Award Types Award Type [Domain] Non-PEO NEO Average Compensation Actually Paid Amount Non-PEO NEO Average Compensation Actually Paid Amount Warrants issued (in shares) Class of Warrant or Right, Outstanding 2026 Lessee, Operating Lease, Liability, to be Paid, Remainder of Fiscal Year Fair Value Measurements Fair Value Disclosures [Text Block] Level 3 Fair Value, Inputs, Level 3 [Member] Variable Interest Entity [Table] Variable Interest Entity [Table] Investment in securities, liabilities, cost Alternative Investments, Investment in Securities, Liabilities, Cost Alternative Investments, Investment in Securities, Liabilities, Cost Supplementary cash flow information: Supplemental Cash Flow Information [Abstract] Treasury stock acquired - share repurchase program (in shares) Treasury stock acquired - share repurchase program (in shares) Treasury Stock, Shares, Acquired Accounts payable and accrued expenses Due to affiliates Accounts Payable and Accrued Liabilities PEO Name PEO Name Total payments Liability for Unpaid Claims and Claims Adjustment Expense, Claims Paid Accrued expenses and other liabilities Accrued Liabilities and Other Liabilities Income taxes paid Income Tax Paid, before Refund Received Long-Lived Asset, Class [Axis] Long-Lived Asset, Class [Axis] Other assets Due from affiliates Other Assets Stock Price or TSR Estimation Method Stock Price or TSR Estimation Method [Text Block] Ceded commissions Deferred Policy Acquisition Cost, Capitalization, Ceded Commissions Deferred Policy Acquisition Cost, Capitalization, Ceded Commissions Entity Tax Identification Number Entity Tax Identification Number Legal Entity [Axis] Legal Entity [Axis] Share-based compensation expense, tax benefit Share-Based Payment Arrangement, Expense, Tax Benefit Treasury stock acquired - share repurchase program Aggregate repurchase price Treasury Stock, Value, Acquired, Cost Method Product Concentration Risk Product Concentration Risk [Member] Investment in securities, liabilities, percentage of stockholders' equity Alternative Investments, Investment in Securities, Liabilities, Percentage of Stockholders' Equity Alternative Investments, Investment in Securities, Liabilities, Percentage of Stockholders' Equity Exercised (in dollars per share) Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price Cash and cash equivalents, at beginning of period Cash and cash equivalents, at end of period Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation Direct Policyholder Benefits and Claims Incurred, Direct Treasury stock reissued related to share-based compensation Stock Issued During Period, Value, Treasury Stock Reissued Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Net change Deferred Policy Acquisition Costs, Period Increase (Decrease) Loans to affiliates Payments to Fund Long-Term Loans to Related Parties Aggregate Erroneous Compensation Not Yet Determined Aggregate Erroneous Compensation Not Yet Determined [Text Block] Material Terms of Trading Arrangement Material Terms of Trading Arrangement [Text Block] Non-NEOs Non-NEOs [Member] Vesting Date Fair Value of Equity Awards Granted and Vested in Covered Year Vesting Date Fair Value of Equity Awards Granted and Vested in Covered Year [Member] Annual fixed fee (as a percent) Management Fee, Percent Fee, Annual Rate Management Fee, Percent Fee, Annual Rate Organization Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block] Net lease (income) Lease, Cost Fixed-maturity securities, available-for-sale Fixed Maturity Securities, Available-For-Sale [Member] Fixed Maturity Securities, Available-For-Sale Limited partners Limited Partners' Capital Account Related party transaction amount Related Party Transaction, Amounts of Transaction Investments in affiliates, cost Investments in Affiliates, Amortized Cost Investments in Affiliates, Amortized Cost Leases Lessee, Operating Leases [Text Block] Due after five years through ten years Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, after Year 5 Through 10 Basic (in dollars per share) Earnings per share - basic (in dollars per share) Earnings Per Share, Basic Letter Agreement Letter Agreement [Member] Letter Agreement Schedule of Outstanding and Exercisable Disclosure of Share-Based Compensation Arrangements by Share-Based Payment Award [Table Text Block] Payments for share repurchases Cash contribution Payments for Repurchase of Common Stock Statistical Measurement [Axis] Statistical Measurement [Axis] Insider Trading Arrangements [Line Items] Award Type Award Type [Axis] Named Executive Officers, Footnote Named Executive Officers, Footnote [Text Block] Cost or Amortized Cost Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, after Allowance for Credit Loss Unrealized gains (losses), net of taxes Unrealized (losses) gains arising during the period, net of taxes Other Comprehensive Income (Loss), Available-for-Sale Securities Adjustment, Net of Tax, Portion Attributable to Parent Retained earnings Retained Earnings (Accumulated Deficit) Product and Service [Axis] Product and Service [Axis] Amortization of policy acquisition costs Deferred Policy Acquisition Costs, Amortization Expense Equity securities Equity Securities, FV-NI Partners' capital: Partners' Capital [Abstract] Aggregate Change in Present Value of Accumulated Benefit for All Pension Plans Reported in Summary Compensation Table Aggregate Change in Present Value of Accumulated Benefit for All Pension Plans Reported in Summary Compensation Table [Member] Awards Close in Time to MNPI Disclosures Awards Close in Time to MNPI Disclosures [Table] Common Stock Common Stock [Member] Other comprehensive (losses) income Other Comprehensive Income (Loss), Net of Tax, Rounded Other Comprehensive Income (Loss), Net of Tax, Rounded Operating lease cost Operating Lease, Cost Compensation Actually Paid vs. Company Selected Measure Compensation Actually Paid vs. Company Selected Measure [Text Block] Cover [Abstract] Reclassifications and Statement of Cash Flows Presentation Reclassification, Comparability Adjustment [Policy Text Block] Insurance [Abstract] Loans to affiliates Advances to Affiliate % of GWP Concentration Risk, Percentage Concentration Risk Benchmark [Axis] Concentration Risk Benchmark [Axis] Equity Awards Adjustments Equity Awards Adjustments [Member] Total liabilities, stockholders' equity and non-controlling interest Liabilities and Equity Deferred Policy Acquisition Costs Deferred Policy Acquisition Costs [Text Block] ZFSG ZFSG [Member] ZFSG Incentive allocation Incentive Allocation Incentive Allocation NQSOs Share-Based Payment Arrangement, Option [Member] Non-controlling interest - General Partner Equity, Attributable to Noncontrolling Interest Segments [Axis] Segments [Axis] Additional 402(v) Disclosure Additional 402(v) Disclosure [Text Block] ZIS Board Letter ZIS Board Letter [Member] ZIS Board Letter Related and Nonrelated Parties [Domain] Related and Nonrelated Parties [Domain] Tabular List, Table Tabular List [Table Text Block] Vesting [Axis] Vesting [Axis] Additional paid-in capital Additional Paid in Capital Reinsurance recoverable on unpaid losses and loss adjustment expenses, beginning balance Reinsurance recoverable on unpaid losses and loss adjustment expenses, ending balance Total reinsurance recoverable on unpaid losses and allocated loss adjustment expenses Reinsurance Recoverable for Unpaid Claims and Claims Adjustments Reserves for Unpaid Losses and Loss Adjustment Expenses Liability for Future Policy Benefits and Unpaid Claims Disclosure [Text Block] Total Stock- holders' Equity Parent [Member] Short-term investments Short-Term Investments [Member] Name Awards Close in Time to MNPI Disclosures, Individual Name Real Estate Properties [Line Items] Real Estate Properties [Line Items] Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested [Member] Outstanding Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Intrinsic Value Ceded written premiums Ceded Ceded Premiums Written Forfeited (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeited in Period Long-Lived Asset, Class [Domain] Long-Lived Asset, Class [Domain] Preferred stock, shares authorized (in share) Preferred Stock, Shares Authorized Property, Plant, and Equipment [Table] Property, Plant, and Equipment [Table] Investment in securities, liabilities, fair value Alternative Investments, Investment in Securities, Liabilities, Fair Value Alternative Investments, Investment in Securities, Liabilities, Fair Value Preferred stock, $0.001 par value, 100,000,000 shares authorized and none issued or outstanding. Preferred Stock, Value, Issued Adjustment to Compensation: Adjustment to Compensation [Axis] Rule 10b5-1 Arrangement Terminated Rule 10b5-1 Arrangement Terminated [Flag] Aggregate Erroneous Compensation Amount Aggregate Erroneous Compensation Amount Cash paid for interest Interest Paid, Excluding Capitalized Interest, Operating Activity Statement of Cash Flows [Abstract] Weighed-average participating securities (in shares) Weighted Average Number of Shares Outstanding, Participating Securities Weighted Average Number of Shares Outstanding, Participating Securities Purchase price Treasury Stock , Value, Acquired, Excluding Excise Tax, Cost Method Treasury Stock , Value, Acquired, Excluding Excise Tax, Cost Method Aggregate Available Trading Arrangement, Securities Aggregate Available Amount Total assets Assets, Fair Value Disclosure Additional investment of partnership Initial investment in limited partnership interests Payments to Acquire Limited Partnership Interests Name Measure Name Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward] Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward] Income Taxes Income Tax Disclosure [Text Block] Pay vs Performance Disclosure [Line Items] Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV [Domain] Pay vs Performance Disclosure Pay vs Performance Disclosure [Table] Additional Paid-in Capital Additional Paid-in Capital [Member] Entity Filer Category Entity Filer Category Total fair value Total, Fair Value Debt Securities, Available-for-Sale, Unrealized Loss Position Licensing fee expense Licensing Fee Expense Licensing Fee Expense Name Trading Arrangement, Individual Name Cash and cash equivalents Cash Cash and Cash Equivalent Schedule of Unvested Non Qualified Stock Options Roll Forward Schedule of Stock Options Roll Forward [Table Text Block] Concentration Risk Benchmark [Domain] Concentration Risk Benchmark [Domain] Company Selected Measure Amount Company Selected Measure Amount Schedule of Premium Receivable, Allowance for Credit Loss Premium Receivable, Allowance for Credit Loss [Table Text Block] Gross realized gains: Realized Investment Gain Realized Investment Gain Investments, Debt and Equity Securities [Abstract] Earned premiums: Premiums Earned, Net [Abstract] Schedule of Realized and Unrealized Gain (Loss) Gain (Loss) on Securities [Table Text Block] Entity Address, Address Line Two Entity Address, Address Line Two Issuance of common stock under share-based compensation plan (in shares) Shares Issued, Shares, Share-Based Payment Arrangement, after Forfeiture Net income Net income (loss) Net income Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Gross investment income Gross Investment Income, Operating Weighted-average remaining lease term — operating leases Operating Lease, Weighted Average Remaining Lease Term Non-PEO NEO Non-PEO NEO [Member] Entity Address, Address Line One Entity Address, Address Line One Total expenses Benefits, Losses and Expenses Vested (in dollars per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value Subsidiary, Sale of Stock [Line Items] Subsidiary, Sale of Stock [Line Items] Income tax expense Income Tax Expense (Benefit) Assets held by insurance regulators Assets Held by Insurance Regulators Award Timing Method Award Timing Method [Text Block] Principles of Consolidation Consolidation, Policy [Policy Text Block] Net change in cash and cash equivalents Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Period Increase (Decrease), Including Exchange Rate Effect and Discontinued Operation Forgone Recovery, Explanation of Impracticability Forgone Recovery, Explanation of Impracticability [Text Block] Numerator: Net Income (Loss) Attributable to Parent [Abstract] Premiums receivable, net of allowance for credit losses of $10,860 in 2026 and $8,754 in 2025 Premiums Receivable, Net Gross realized (losses): Realized Investment Loss Realized Investment Loss Fixed interest rate Loans Receivable, Fixed Interest Rate Loans Receivable, Fixed Interest Rate Variable Interest Entity, Primary Beneficiary Variable Interest Entity, Primary Beneficiary [Member] Net income attributable to stockholders Net income attributable to stockholders Net Income (Loss) Attributable to Parent Erroneous Compensation Analysis Erroneous Compensation Analysis [Text Block] Statement [Table] Statement [Table] Adjustments and reconciling items Segment Reporting, Reconciling Item, Excluding Corporate Nonsegment [Member] Tranche 2 Share-Based Payment Arrangement, Tranche Two [Member] Restatement Determination Date: Restatement Determination Date [Axis] Underwriting, acquisition and insurance expenses Total underwriting, acquisition and insurance expenses Underwriting Acquisition and Insurance Expenses Underwriting Acquisition and Insurance Expenses Interest income Investment Income, Interest Exercisable, (in dollars per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Weighted Average Exercise Price Income tax payable Accrued Income Taxes Revenues Revenues [Abstract] Stockholders' equity: Temporary Equity [Abstract] Pension Benefits Adjustments, Footnote Pension Benefits Adjustments, Footnote [Text Block]