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compensation expense Share-Based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount Cash and cash equivalents Cash and Cash Equivalent Company Selected Measure Amount Company Selected Measure Amount Hagerty Reinsurance Limited Hagerty Reinsurance Limited [Member] Hagerty Reinsurance Limited Tax receivable Income Taxes Receivable Depreciation and amortization Depreciation, Depletion and Amortization Preferred stock, redemption amount Preferred Stock, Redemption Amount Reinsurance retention policy, number of coverage layers Reinsurance Retention Policy, Number Of Coverage Layers Reinsurance Retention Policy, Number Of Coverage Layers Deferred financing costs related to revolving credit facilities Deferred Financing Costs Deferred Financing Costs Weighted average lease term Operating Lease, Weighted Average Remaining Lease Term Non-PEO NEO Non-PEO NEO [Member] Customer Concentration Risk Customer Concentration Risk [Member] Award Timing Method Award Timing Method [Text Block] Change in cash and cash equivalents and restricted 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] Tranche Three Share-Based Payment Arrangement, Tranche Three [Member] Long-term Debt, Type [Axis] Long-Term Debt, Type [Axis] Erroneous Compensation Analysis Erroneous Compensation Analysis [Text Block] Restatement Determination Date: Restatement Determination Date [Axis] Debt instrument, convertible, threshold consecutive trading days Debt Instrument, Convertible, Threshold Consecutive Trading Days NET INCOME (LOSS) ATTRIBUTABLE TO CLASS A COMMON STOCKHOLDERS Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent REVENUE: Revenues [Abstract] TEMPORARY EQUITY Temporary Equity [Abstract] Pension 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Securities, Available-for-Sale, Accumulated Gross Unrealized Loss, before Tax Prepaid software-as-a-service ("SaaS") implementation costs Prepaid Software Implementation Costs Prepaid Software Implementation Costs Loss Contingencies [Table] Loss Contingencies [Table] Investments [Domain] Investments [Domain] Causes of Increase (Decrease) in Liability for Unpaid Claims and Claims Adjustment Expense [Table] Liability for Unpaid Claim and Claim Adjustment Expense, Change [Table] Change in TRA Liability Change in TRA Liability Gain (Loss) related To Tax Receivable Agreement Liability Gain (Loss) related To Tax Receivable Agreement Liability Adjustment to Non-PEO NEO Compensation Footnote Adjustment to Non-PEO NEO Compensation Footnote [Text Block] Entity Address, State or Province Entity Address, State or Province State licenses Licensing Agreements [Member] Purchases of equity securities Payments to Acquire Equity Securities, FV-NI PEO Total Compensation Amount PEO Total Compensation Amount Foreign currency translation adjustments Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax Basic (in shares) Weighted-average shares of Class A Common Stock outstanding (in shares) Weighted-average shares of Class A Common Stock outstanding, Basic (in shares) Weighted Average Number of Shares Outstanding, Basic Contract assets Contract with Customer, Asset, after Allowance for Credit Loss, Current Schedule of Related Party Transactions Schedule of Related Party Transactions [Table Text Block] Loss Contingencies [Line Items] Loss Contingencies [Line Items] Policy acquisition costs, net Policy acquisition costs, net Policy Acquisition Costs, Net Policy Acquisition Costs, Net Deferred acquisition costs, net Increase (Decrease) in Deferred Policy Acquisition Costs 2029 Lessee, Operating Lease, Liability, to be Paid, Year Four Payout percentage Share-Based Compensation Arrangement by Share-Based Payment Award, Payout Percentages Share-Based Compensation Arrangement by Share-Based Payment Award, Payout Percentages Amortization of gain on loss portfolio transfer Amortization Of Gain On Loss Portfolio Transfer Amortization Of Gain On Loss Portfolio Transfer 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 Prepaid selling, general, and administrative expenses Prepaid Selling, General And Administrative Expense Prepaid Selling, General And Administrative Expense THG LLC THG LLC [Member] THG LLC Schedule of Supplemental Cash Flow Information Schedule of Cash Flow, Supplemental Disclosures [Table Text Block] Reinsured risk, percentage Reinsurance, Reinsured Risk, Percentage Non-cash lease expense Non-cash Lease Expense Non-cash Lease Expense Loans, renewal option, term (in year) Financing Receivable, Renewal Option, Term Financing Receivable, Renewal Option, Term Notes Receivable Loans, Notes, Trade and Other Receivables Disclosure [Text Block] BAC Credit Facility BAC Credit Facility [Member] BAC Credit Facility Document Information [Line Items] Document Information [Line Items] Essentia Essentia [Member] Essentia Award Timing MNPI Disclosure Award Timing MNPI Disclosure [Text Block] Vested (in shares) Vested (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period Basis of Presentation Basis of Accounting, Policy [Policy Text Block] Payment of Series A Convertible Preferred Stock dividends Payments of Ordinary Dividends, Preferred Stock and Preference Stock Class of Stock [Axis] Class of Stock [Axis] 2024 Performance Restricted Stock Unit Agreement 2024 Performance Restricted Stock Unit Agreement [Member] 2024 Performance Restricted Stock Unit Agreement Net income (loss) available to Class A Common Stockholders Net income (loss) available to Class A Common Stockholders, Basic Net Income (Loss) Available to Common Stockholders, Basic Accumulated amortization Intangible Asset, Finite-Lived, Accumulated Amortization Sublease revenue Sublease Income Receivable [Domain] Receivable [Domain] Maximum borrowing capacity Line of Credit Facility, Maximum Borrowing Capacity Investment expenses Investment Income, Investment Expense Accounting Standards Not Yet Adopted New Accounting Pronouncements, Policy [Policy Text Block] Capital expenditures Capital Expenditures Incurred but Not yet Paid Non-controlling Interest Noncontrolling Interest [Member] Debt, net Long-Term Debt Hagerty, Inc. Hagerty, Inc. [Member] Hagerty, Inc. Southern California Southern California [Member] Southern California Net Cash Used in Investing Activities Cash Provided by (Used in) Investing Activity, Including Discontinued Operation Equity Awards Adjustments, Excluding Value Reported in Compensation Table Equity Awards Adjustments, Excluding Value Reported in the Compensation Table [Member] Unrecognized tax benefits Unrecognized Tax Benefits Stockholders' Equity Equity [Text Block] Temporary equity, shares outstanding (in shares) Temporary equity, beginning balance (in shares) Temporary equity, ending balance (in shares) Temporary Equity, Shares Outstanding Security Exchange Name Security Exchange Name Reserves for Unpaid Losses and Loss Adjustment Expenses Insurance Disclosure [Text Block] Issuance of shares of Class A Common Stock resulting from the vesting of RSUs (Refer to Note 17) Noncash Transaction, Issuance of Common Stock resulting From Vesting Of RSU Noncash Transaction, Issuance of Common Stock resulting From Vesting Of RSU Schedule of Assets and Liabilities of Consolidated Variable Interest Entities Condensed Balance Sheet [Table Text Block] 12 months or longer, Estimated fair value Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer Statement of Comprehensive Income [Abstract] Ceding commissions payable Ceded Premiums Payable Various reinsurers Various Reinsurers [Member] Various Reinsurers Name Outstanding Recovery, Individual Name Award Timing, How MNPI Considered Award Timing, How MNPI Considered [Text Block] Variable Interest Entities Consolidation, Variable Interest Entity, Policy [Policy Text Block] Segment Reporting and Disaggregated Revenue Segment Reporting And Disaggregated Revenue [Text Block] Segment Reporting And Disaggregated Revenue Consignor Advances Consignor Advances Receivable [Member] Consignor Advances Receivable Geographical [Domain] Geographical [Domain] Prior Year End Fair Value of Equity Awards Granted in Any Prior Year that Fail to 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Related Party Transactions [Abstract] Gross investment income Investment Income, Interest and Dividend Compensation Amount Outstanding Recovery Compensation Amount Individual: Individual [Axis] Diluted (in shares) Weighted-average shares of class A common stock outstanding (in shares) Weighted-average shares of class A common stock outstanding, Diluted (in shares) Weighted Average Number of Shares Outstanding, Diluted Direct Sales Channel, Directly to Consumer [Member] Disaggregation of Revenue [Line Items] Disaggregation of Revenue [Line Items] Employee Stock Ownership Plan (ESOP) Name [Axis] Employee Stock Ownership Plan (ESOP) Name [Axis] Entity Emerging Growth Company Entity Emerging Growth Company Related Party Transaction [Line Items] Related Party Transaction [Line Items] Underlying Security Market Price Change Underlying Security Market Price Change, Percent Less: imputed interest Lessee, Operating Lease, Liability, Undiscounted Excess Amount Operating Lease, Liability, 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Reinsurance [Line Items] SEC Schedule, 12-17, Insurance Companies, Reinsurance [Line Items] Organization, Consolidation and Presentation of Financial Statements [Abstract] State Farm State Farm [Member] State Farm Indefinite-lived Intangible Assets, Major Class Name [Domain] Intangible Asset, Indefinite-Lived, Class [Domain] Total lease payments Lessee, Operating Lease, Liability, to be Paid Distributions paid to non-controlling interest unit holders Payments Of Distributions To Noncontrolling Interest Payments Of Distributions To Noncontrolling Interest Changes in assets and liabilities: Increase (Decrease) in Other Operating Assets and Liabilities, Net [Abstract] Beginning balance (in dollars per share) Ending balance (in dollars per share) Weighted average grant-date fair value per share (in dollars per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value All Executive Categories All Executive Categories [Member] Premium percentage Limited Liability Company Or Limited Partnership, Members Or Limited Partners, Premium Percentage Limited Liability Company Or Limited Partnership, Members Or Limited Partners, Premium Percentage Pension Adjustments Service Cost Pension Adjustments Service Cost [Member] Other comprehensive income (loss), net of tax: Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent [Abstract] Convertible preferred stock Per-share purchase price (in dollars per shares) Preferred Stock, Convertible, Conversion Price Schedule of Earnings Per Share, Basic and Diluted Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Debt Disclosure [Abstract] Minimum Minimum [Member] Investment Type [Axis] Investment Type [Axis] Total commission and fee revenue Commission and fee revenue Commission Revenue And Fee Revenue [Member] Commission Revenue And Fee Revenue Class of Stock [Roll Forward] Class of Stock, 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[Member] Equity securities Equity Securities, FV-NI, Restricted Prior accident years Liability for Unpaid Claims and Claims Adjustment Expense, Claims Paid, Prior Years Repayments of debt Repayments of Long-Term Debt Awards Close in Time to MNPI Disclosures, Table Awards Close in Time to MNPI Disclosures [Table Text Block] Fundamental Transaction Fundamental Transaction [Member] Fundamental Transaction Equity Component [Domain] Equity Component [Domain] Deferred acquisition costs, net Deferred Policy Acquisition Cost Consideration received on transaction Sale of Stock, Consideration Received on Transaction Adoption Date Trading Arrangement Adoption Date Counterparty Name [Domain] Counterparty Name [Domain] Common stock, conversion ratio Common Stock, Convertible, Conversion Ratio Common Stock, Convertible, Conversion Ratio Title Trading Arrangement, Individual Title Forgone Recovery due to Disqualification of Tax Benefits, Amount Forgone Recovery due to Disqualification of Tax Benefits, Amount Optional Term Redemption Optional Term Redemption [Member] Optional Term Redemption Accounting Policies [Abstract] Restatement does not require Recovery Restatement Does Not Require Recovery [Text Block] Risk-free interest rate Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Risk Free Interest Rate Total lease liabilities Operating Lease, Liability Finance revenue Financing Revenue Financing Revenue Other financing activities Proceeds from (Payment for) Other Financing Activity Insider Trading Policies and Procedures Adopted Insider Trading Policies and Procedures Adopted [Flag] Adjustment for potentially dilutive THG units (in shares) Incremental Common Shares Attributable to Dilutive Effect of Equity Unit Purchase Agreements Performance Condition Performance Shares Performance Condition Performance Shares [Member] Performance Condition Performance Shares Loans Receivable Loans Receivable [Member] Selling, general, and 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Combination [Axis] Net Cash Provided by Operating Activities Cash Provided by (Used in) Operating Activity, Including Discontinued Operation Prior accident years Prior Year Claims and Claims Adjustment Expense Issuance of notes receivable Payments to Acquire Notes Receivable Income Statement [Abstract] Issuance of shares under employee plans (in shares) Stock Issued During Period, Shares, Employee Stock Purchase Plans Document Transition Report Document Transition Report Net investment gains Net investment gains Gain (Loss) on Investments Deferred tax assets Deferred Income Tax Assets, Net EXPENSES: Operating Expenses [Abstract] Collection of notes receivable Proceeds from Collection of Notes Receivable Stock Appreciation Rights (SARs) Stock Appreciation Rights (SARs) [Member] Schedule of Cost and Accumulated Amortization Intangible Asset, Finite-Lived [Table Text Block] Hurricane Hurricane [Member] Causes of Increase (Decrease) in Liability for Unpaid Claims and Claims Adjustment Expense [Line Items] Causes of Increase (Decrease) in Liability for Unpaid Claims and Claims Adjustment Expense [Line Items] City Area Code City Area Code Document Information [Table] Document Information [Table] Subsequent Events Subsequent Events [Text Block] Name Forgone Recovery, Individual Name Bennetts Motorcycling Services Limited Bennetts Motorcycling Services Limited [Member] Bennetts Motorcycling Services Limited Non-GAAP Measure Description Non-GAAP Measure Description [Text Block] Weighted Average Grant Date Fair Value Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract] Entity [Domain] Entity [Domain] Preferred stock, shares issued (in shares) Preferred Stock, Shares Issued Markel Fronting Arrangement [Abstract] Markel Fronting Arrangement State Farm Term Loan State Farm Term Loan Facility [Member] State Farm Term Loan Facility Stock issued during period, 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[Domain] Equity Transaction Type [Domain] Revision of Prior Period [Domain] Revision of Prior Period [Domain] Forfeited (in dollars per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value Reinsurance, amount retained, per event Reinsurance, Amount Retained, Per Event Series A Convertible Preferred Stock Series A Preferred Stock [Member] Erroneously Awarded Compensation Recovery Erroneously Awarded Compensation Recovery [Table] Change in net unrealized gain (loss) on available-for-sale investments OCI, Debt Securities, Available-for-Sale, Unrealized Holding Gain (Loss), before Adjustment, after Tax Payments of debt issuance costs Payments of Debt Issuance Costs Effect of foreign currency rate changes Liability for Unpaid Claims and Claims Adjustment Expense, Foreign Currency Translation Gain (Loss) Entity Current Reporting Status Entity Current Reporting Status Net Cash Provided by Financing Activities Cash Provided by (Used in) Financing Activity, Including Discontinued Operation Total Shareholder Return Amount Total Shareholder Return Amount SEC Schedule, 12-17, Insurance Companies, Reinsurance [Table] SEC Schedule, 12-17, Insurance Companies, Reinsurance [Table] Schedule of Changes In The Deposit Liability Schedule of Changes In The Deposit Liability [Table Text Block] Schedule of Changes In The Deposit Liability Ownership percentage by Hagerty, Inc Limited Liability Company (LLC) or Limited Partnership (LP), Managing Member or General Partner, Ownership Interest Adjustments to reconcile net income (loss) to net cash from operating activities: Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity [Abstract] Temporary equity, par value (in dollars per share) Temporary Equity, Par or Stated Value Per Share Property and equipment, net Property, Plant, and Equipment, after Accumulated Depreciation, Depletion, and 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Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months Other Performance Measure, Amount Other Performance Measure, Amount Award Timing MNPI Considered Award Timing MNPI Considered [Flag] Current Fiscal Year End Date Current Fiscal Year End Date Equity interests in Hagerty (in shares) Investment Owned, Balance, Shares Reinsurance Contract [Axis] Reinsurance Contract [Axis] Non-PEO NEO Average Total Compensation Amount Non-PEO NEO Average Total Compensation Amount Issuance of notes receivable Noncash Or Part Noncash Payments To Acquire Notes Receivable Noncash Or Part Noncash Payments To Acquire Notes Receivable Change in Fair Value as of Vesting Date of Prior Year Equity Awards Vested in Covered Year Change in Fair Value as of Vesting Date of Prior Year Equity Awards Vested in Covered Year [Member] Entity File Number Entity File Number Schedule of Contractual Maturities of the Company's Available-for-Sale Investments Investments Classified by Contractual Maturity Date [Table Text Block] Schedule of Unpaid Losses and Loss Adjustment Expenses Schedule of Liability for Unpaid Claims and Claims Adjustment Expense [Table Text Block] Distributions paid to non-controlling interest unit holders Non-controlling interest unit holders Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders Recovery of Erroneously Awarded Compensation Disclosure [Line Items] Measure: Measure [Axis] (Accretion) amortization of discount and premium, net Amortization of Debt Discount (Premium) Earned premium, net Earned premium, net Net Premiums Earned, Net Equity Components [Axis] Equity Components [Axis] Costs to obtain contracts with customers Capitalized Contract Cost, Net Cash paid for income taxes Income Tax Paid, after Refund Received Class A Common Stock Common Class A [Member] Entity Interactive Data Current Entity Interactive Data Current Net (income) loss attributable to non-controlling interest Net Income (Loss) Attributable to 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Withholdings Stock Issued During Period, Value, Employee Stock Purchase Plan, Net Of Tax Withholdings 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] Summary of Significant Accounting Policies Significant Accounting Policies [Text Block] Tax benefit distributions to noncontrolling interest holders, percent Tax Receivable Agreement, Tax Benefit Distributions To Noncontrolling Interest Holders, Percent Tax Receivable Agreement, Tax Benefit Distributions To Noncontrolling Interest Holders, Percent Cash and cash equivalents and restricted cash and cash equivalents Cash and Cash Equivalents [Member] Statement of Stockholders' Equity [Abstract] Proceeds from debt, net of issuance costs Proceeds from Issuance of Long-Term Debt Local Phone Number Local Phone Number Supplemental Balance Sheet and Cash Flow Information Additional Financial Information Disclosure [Text Block] Temporary equity, shares authorized (in shares) Temporary Equity, Shares Authorized INCOME (LOSS) BEFORE TAXES (Loss) Income before taxes Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Collection of notes receivable Noncash Or Part Noncash Proceeds From Collection Of Notes Receivable Noncash Or Part Noncash Proceeds From Collection Of Notes Receivable Commitments and Contingencies Commitments and Contingencies Debt Instrument, Redemption, Period [Domain] Debt Instrument, Redemption, Period [Domain] Antidilutive Securities, Name [Domain] Antidilutive Securities, Name [Domain] Changed Peer Group, Footnote Changed Peer Group, Footnote [Text Block] 2030 Intangible Asset, Finite-Lived, Estimated Amortization Expense, Year Four Executive Category: Executive Category [Axis] Receivable Type [Axis] Receivable Type [Axis] Schedule of Restricted Stock Units Activity Schedule of Nonvested Restricted Stock Units 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[Text Block] Restricted cash and cash equivalents Restricted Cash and Cash Equivalent, Current 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] Comprehensive income (loss) Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest Debt Instrument [Axis] Debt Instrument [Axis] Measurement Frequency [Domain] Measurement Frequency [Domain] Share-based compensation expense Share-Based Payment Arrangement, Noncash Expense Lease cost, net Lease, Cost Stockholders' Equity Members' Equity Notes Disclosure [Text Block] Basic (in dollars per share) Basic earnings (loss) per share (in dollars per share) Earnings Per Share, Basic Markel Fronting Arrangement Markel Fronting Arrangement [Text Block] Markel Fronting Arrangement Insider Trading Arrangements [Line Items] Debt, net Debt, net Long-Term Debt, Excluding Current Maturities Related party 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Agreement, Tax Benefit Retained By Parent, Percent Tax Receivable Agreement, Tax Benefit Retained By Parent, Percent Undistributed earnings reallocated to Series A Convertible Preferred Stock Undistributed Earnings (Loss) Allocated to Participating Securities, Diluted Commission and fee revenue Commission And Fee Revenue [Member] Products And Services, Commission And Fee Revenue [Member] Preferred stock, shares authorized (in shares) Preferred Stock, Shares Authorized On or after the Tenth Anniversary Debt Instrument, Redemption, Period fourteen [Member] Debt Instrument, Redemption, Period fourteen Class of Stock [Domain] Class of Stock [Domain] Statement of Cash Flows [Abstract] Alliance Agreement Alliance Agreement [Member] Alliance Agreement On or after the Ninth but Prior to Tenth Anniversary Debt Instrument, Redemption, Period Thirteen [Member] Debt Instrument, Redemption, Period Thirteen Due to insurers Due To Insurers Due To Insurers Aggregate Available Trading Arrangement, Securities Aggregate Available Amount Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward] Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward] Taxation Income Tax Disclosure [Text Block] Other Other Noncash Income (Expense) 2030 Lessee, Operating Lease, Liability, to be Paid, Year Five Accretion of Series A Convertible Preferred Stock Preferred Stock, Accretion of Redemption Discount Pay vs Performance Disclosure Pay vs Performance Disclosure [Table] Purchase price Business Combination, Consideration Transferred Entity Filer Category Entity Filer Category Estimated fair value Debt Securities, Available-for-Sale, Unrealized Loss Position Revision of Prior Period [Axis] Revision of Prior Period [Axis] Ceding commissions payable Commission Payable Commission Payable Convertible preferred stock, redemption price, percentage Convertible Preferred Stock, Redemption Price, Percentage Convertible Preferred Stock, Redemption Price, Percentage Restricted 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in Exchange for Operating Lease Liability Total expenses 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 Income tax (expense) benefit Income tax (expense) benefit Income Tax Expense (Benefit) Total restricted assets Restricted Cash and Investments Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items] Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items] Principles of Consolidation Consolidation, Policy [Policy Text Block] Premiums receivable Premiums receivable Premiums Receivable, Net ​Total Other Intangible Assets, Net Variable Interest Entity, Primary Beneficiary Variable Interest Entity, Primary Beneficiary [Member] Employee Stock Ownership Plan (ESOP), Plan [Domain] Employee 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