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Amended increase in shares reserved for issuance (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized Net Amount Reinsurance, Net Amount [Abstract] Reinsurance, Net Amount [Abstract] option budget Measurement Input Option Budget [Member] Measurement Input Option Budget Maturing On November 15, 2023 Maturing On November 15 2023 [Member] Maturing On November 15 2023 [Member] Sales and repayments Proceeds from Sale and Maturity of Marketable Securities Statutory Information and Dividend Restrictions Statutory Surplus And Subsidiary Dividend Restrictions [Text Block] Statutory surplus and subsidiary dividend restrictions. 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ASSETS ASSETS Assets [Abstract] CARES Act net operating loss carryback Effective Income Tax Rate Reconciliation, CARES Act Net Operating Loss Carryback, Amount Effective Income Tax Rate Reconciliation, CARES Act Net Operating Loss Carryback, Amount Options exercised and conversion of common stock units and restricted stock units Shares Issued, Value, Share-based Payment Arrangement, after Forfeiture Cash paid for amounts included in the measurement of lease liabilities Operating Lease, Payments Annuity contracts: variable, fixed and FHLB funding agreements Net Change Annuities and Investment Certificates [Abstract] Comprehensive Income (Loss) and Accumulated Other Comprehensive Income (Loss) Comprehensive Income (Loss) Note [Text Block] FHLB advances interest rate Federal Home Loan Bank, Advances, Interest Rate Maturing On January 15, 2021 Maturing On January 15 2021 [Member] Maturing On January 15 2021 Increase (decrease) to DAC amortization expense: Adjustment To Deferred Policy Acquisition Cost Amortization Expenses [Abstract] Debt securities, measurement input Debt Securities, Available-for-sale, Measurement Input Amortization of acquisition costs for supplemental policies Amortization Period Of Acquisition Costs Related To Supplemental Policies Amortization Period Of Acquisition Costs Related To Supplemental Policies Granted, Vested, Units (in shares) Share based Compensation Arrangement By Share based Payment Award Equity Instruments Other Than Options Granted In Period Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Granted In Period. Amortization of acquisition costs for individual life contracts, second term Acquisition Costs Amortization In Years For Individual Life Contracts Term Two The number of years over which capitalized acquisition costs are amortized for individual life contracts. Acquisition costs are amortized in proportion to the anticipated premiums over the terms of the insurance policies. Adjustment for performance achievement, Total Outstanding Units (in shares) Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Adjustment For Performance Achievement In Period Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Adjustment For Performance Achievement In Period 2021 Lessee, Operating Lease, Liability, to be Paid, Year One Summary of realized investment gains (losses) Realized Gain (Loss) on Investments [Table Text Block] Guaranteed Insurance Contract, Type of Benefit [Domain] Guaranteed Insurance Contract, Type of Benefit [Domain] Paid claims and claim adjustment expenses SEC Schedule, 12-18, Supplemental Information, Property-Casualty Insurance Underwriters, Paid Claim and Claim Adjustment Expense Options Vested and Exercisable, Forfeited (in shares) Share Based Compensation Arrangement By Share Based Payment Award Options Vested And Exercisable Forfeited In Period Share based compensation arrangement by share based payment award options vested and exercisable forfeited in period. Stock options (in shares) Options Outstanding, Beginning Balance (in shares) Options Outstanding, Ending Balance (in shares) Total Outstanding Options, Options (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number Proceeds received Proceeds From Sale And Maturity Of Marketable Securities (Excluding FHLB Repayments) Proceeds From Sale And Maturity Of Marketable Securities (Excluding FHLB Repayments) 2024 Lessee, Operating Lease, Liability, to be Paid, Year Four Summary of company's fair value hierarchy measured at recurring basis Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block] Deferred policy acquisition costs Increase (Decrease) in Deferred Policy Acquisition Costs AOCI Attributable to Parent, Net of Tax [Roll Forward] AOCI Attributable to Parent, Net of Tax [Roll Forward] Paydowns, maturities and distributions FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityPaydownsAndMaturities Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Paydowns And Maturities Preferred stock, $0.001 par value, authorized 1,000,000 shares; none issued Preferred stock, $0.001 par value, authorized 1,000,000 shares; none issued Preferred Stock, Value, Issued Minimum exercise price (in usd per share) Share-based Payment Arrangement, Option, Exercise Price Range, Lower Range Limit FHLB borrowings Proceeds from Bank Debt Amortization of acquisition costs for property and casualty contracts, second term Amortization Period Of Acquisition Costs Related To Property And Casualty Policy Term Two The period of time over which capitalized acquisition costs are amortized for property and casualty policies. Acquisition costs are amortized over the term of the insurance policy (6 and 12 months). Other comprehensive income (loss), net of tax: Other Comprehensive Income (Loss), Net of Tax [Abstract] Derivatives embedded in fixed indexed annuity products, measurement input Derivative Liability, Measurement Input Common stock, par value (in usd per share) Common Stock, Par or Stated Value Per Share 2023 Defined Benefit Plan, Expected Future Benefit Payment, Year Three Deferred Deferred Income Tax Liabilities (Assets) Deferred income tax assets liabilities. 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Fair value as a percentage of total fixed maturities and equity securities fair value, 12 Months or Less Fair value as percentage of total fixed maturities and equity securities fair value less than 12 months Fair value of positions with a gross unrealized loss for twelve months or less as a percentage of total fixed maturities and equities fair value. Weighted Average Weighted Average [Member] Vesting period for Company contributions Defined Contribution Plan, Vesting Period for Company Contributions Defined Contribution Plan, Vesting Period for Company Contributions Entity Small Business Entity Small Business Consolidation Consolidation, Policy [Policy Text Block] Federal Home Loan Bank Branch [Axis] Federal Home Loan Bank Branch [Axis] Closed-end fund Contract Holder Funds [Member] Year Nine Short-duration Insurance Contracts, Historical Claims Duration, Year Nine GMDB reserve Guaranteed Minimum Death Benefit Reserve Guaranteed minimum death benefit reserve. 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Amendment Flag Amendment Flag Deposits Additions to Contract Holders Funds Weighted average assumptions: Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract] Finite-Lived Intangible Assets, Major Class Name [Domain] Finite-Lived Intangible Assets, Major Class Name [Domain] Beginning balance Ending balance Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability Value Corporate and Other Corporate, Non-Segment [Member] Shares available for grant (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant Remaining minimum amount committed Purchase Commitment, Remaining Minimum Amount Committed Total Variable Annuity Contract Value Distribution Percent Variable annuity contract value distribution percent. Amounts reclassified from AOCI Reclassification from AOCI, Current Period, Net of Tax, Attributable to Parent Societe Generale Societe Generale [Member] non-performance adjustment Measurement Input Non Performance Adjustment [Member] Measurement Input Non Performance Adjustment Debt redemption price, interest discounted at treasury yield margin Debt Instrument, Redemption Price, Interest Discounted At Treasury Yield Margin Debt Instrument, Redemption Price, Interest Discounted At Treasury Yield Margin Deposit asset on reinsurance Deposit Asset On Reinsurance Fair Value Disclosure Deposit Asset On Reinsurance Fair Value Disclosure Measurement Frequency [Axis] Measurement Frequency [Axis] Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] Financial Instruments [Domain] Financial Instruments [Domain] Expected return on plan assets Defined Benefit Plan, Expected Return (Loss) on Plan Assets Aggregate amount of dividends Statutory Accounting Practices, Statutory Amount Available for Dividend Payments Consolidated capital and surplus, statutory basis Statutory Accounting Practices, Statutory Capital and Surplus, Balance Net investment gains (losses) Derivative, Gain (Loss) on Derivative, Net Amortization of: Amortization [Abstract] Fair Value Measurement [Domain] Fair Value Measurement [Domain] Fixed maturity securities, Fair Value, More than 12 Months Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer Value of distribution acquired Distribution Acquired [Member] Distribution Acquired [Member] Losses related to securities sold or paid down during the period Other than Temporary Impairment, Credit Losses Recognized in Earnings, Reductions, Securities Sold Retirement Retirement Annuity Insurance Product Line [Member] Product line consisting of insurance policies providing annuity contracts. Liabilities Derivative Liability [Abstract] SEC Schedule, 12-18, Supplemental Information, Property-Casualty Insurance Underwriters [Abstract] SEC Schedule, 12-18, Supplemental Information, Property-Casualty Insurance Underwriters [Abstract] Renewal term Lessee, Operating Lease, Renewal Term Unrecognized share-based compensation expense, nonvested options Share-based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount Percentage of Amount Assumed to Net SEC Schedule, 12-17, Insurance Companies, Reinsurance, Life Insurance in Force, Percentage Assumed to Net Property, Plant and Equipment, Type [Axis] Long-Lived Tangible Asset [Axis] Ceded to Other Companies Reinsurance, Ceded to Other Companies [Abstract] Reinsurance, Ceded to Other Companies [Abstract] Life insurance future policy benefit reserve Deferred Tax Liabilities, Deposit Asset On Reinsurance Deferred Tax Liabilities, Deposit Asset On Reinsurance Income Statement Location [Domain] Income Statement Location [Domain] 2022 Lessee, Operating Lease, Liability, to be Paid, Year Two Minimum statutory-basis capital and surplus Statutory Accounting Practices, Statutory Capital and Surplus Required Cash flows from financing activities Net Cash Provided by (Used in) Financing Activities [Abstract] Schedule of components lease expense Lease, Cost [Table Text Block] Outstanding prior to 2011 Short-duration Insurance Contracts, Liability for Unpaid Claims and Allocated Claim Adjustment Expense, Net, Not Separately Presented Retirement Retirement [Member] 2023 Lessee, Operating Lease, Liability, to be Paid, Year Three FNMA Federal National Mortgage Association Certificates and Obligations (FNMA) [Member] Plan Name [Axis] Plan Name [Axis] Amortization of acquisition costs for individual life contracts, fourth term Acquisition Costs Amortization In Years For Individual Life Contracts Term Four The number of years over which capitalized acquisition costs are amortized for individual life contracts. Acquisition costs are amortized in proportion to the anticipated premiums over the terms of the insurance policies. Citigroup Inc. Citigroup Inc [Member] Net investment (gains) losses Gain (Loss) on Sale of Investments Total assets Assets Assets Automobile liability Auto Liability [Member] Impairment of infinite lived intangible assets Impairments Impairment of Intangible Assets, Indefinite-lived (Excluding Goodwill) Issuances Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Issuances Funded status of the defined benefit, supplemental retirement pension plans and postretirement benefits other than pensions Schedule of Net Funded Status [Table Text Block] Exercise Price Range [Domain] Exercise Price Range [Domain] Short tail coverage reserves as a percentage of total reserves Short Tail Coverage Reserves As A Percentage Of Total Reserves. Short Tail Coverage Reserves As A Percentage Of Total Reserves. Foreign government bonds Debt Security, Government, Non-US [Member] Net income Proceeds from Insurance Premiums Collected RSUs related to incentive compensation (in shares) Beginning balance, Total Outstanding, Units (in shares) Ending balance, Total Outstanding, Units (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number Unpaid Claims and Claim Expenses Liability for Future Policy Benefits and Unpaid Claims Disclosure [Text Block] Catastrophic Event [Axis] Catastrophic Event [Axis] 2019 Short-Duration Insurance Contract, Accident Year 2019 [Member] Prior service cost Defined Benefit Plan, Amortization of Prior Service Cost (Credit) Summary of guaranteed minimum death benefit Summary Of Guaranteed Minimum Death Benefit [Table Text Block] Summary of guaranteed minimum death benefit. Unpaid Claims and Claim Expenses Unpaid Policy Claims and Claims Adjustment Expense, Policy [Policy Text Block] Insurance liabilities Increase (Decrease) in Insurance Liabilities Qualified Plan Qualified Plan [Member] Investments, Debt and Equity Securities [Abstract] Investments, Debt and Equity Securities [Abstract] Premiums written and contract deposits, Ceded to Other Companies Ceded Insurance Premiums Written And Contract Deposits Insurance premiums written and contract deposits assumed by another insurer as a result of reinsurance arrangements. Employee share-based compensation Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Payment Arrangement, Amount Losses incurred for catastrophe claims, carrying amount Loss from Catastrophes Commercial mortgage-backed securities Commercial Mortgage Backed Securities [Member] Amount of maximum individual life insurance risk retained Amount Of Maximum Individual Life Insurance Risk Retained Amount of maximum individual life insurance risk retained. Fair Value Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling Maturity, Fair Value [Abstract] Total liabilities Liabilities Life policy accounts Net Change Contract Holders Funds [Abstract] Sales Sales [Member] Retirement Plan Type [Axis] Retirement Plan Type [Axis] Expected volatility (based on historical volatility) Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate Less imputed interest Lessee, Operating Lease, Liability, Undiscounted Excess Amount Distribution of Company's fixed maturity portfolio by estimated expected maturity Carrying value, fair value and fair value hierarchy of financial assets and financial liabilities Carrying value, fair value and fair value hierarchy of financial assets and financial liabilities. Fixed maturity securities, Fair Value, Total Debt Securities, Available-for-sale, Unrealized Loss Position 2013 Short-duration Insurance Contracts, Accident Year 2013 [Member] Ceded to Other Companies SEC Schedule, 12-17, Insurance Companies, Reinsurance, Life Insurance in Force, Ceded Commitments and Contingencies Disclosure [Abstract] Commitments and Contingencies Disclosure [Abstract] Level 1 Fair Value, Inputs, Level 1 [Member] Financial Assets Financial Assets Financial assets. Fixed maturity securities, Fair Value, 12 Months or Less Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months Investment contract and policy reserves Total Liability for Future Policy Benefit, before Reinsurance Total Outstanding Units Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] Other operating assets and liabilities Increase (Decrease) in Other Operating Assets and Liabilities, Net Range of Option Prices per Share, Forfeited (in usd per share) Share Based Compensation Shares Forfeited Under Stock Option Plans Exercise Price Range Share based compensation shares forfeited under stock option plans exercise price range. Public utilities Public Utility, Equities [Member] Additional paid-in capital Additional Paid-in Capital [Member] Other assets Other Assets Operating expenses Operating Expenses Excluding Amortization Of Intangible Assets Operating Expenses Excluding Amortization Of Intangible Assets Condensed Financial Statements, Captions [Line Items] Condensed Financial Statements, Captions [Line Items] Other Other Operating Activities, Cash Flow Statement Schedule IV Reinsurance SEC Schedule, 12-17, Insurance Companies, Reinsurance [Text Block] FHLB funding agreements Federal Home Loan Bank Funding Agreements Represents the federal home loan bank funding agreements. Number of position with a gross unrealized loss, more than 12 months Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions Deferred tax assets Deferred Tax Assets, Net [Abstract] Income Tax Disclosure [Abstract] Income Tax Disclosure [Abstract] Other asset-backed securities Other asset-backed securities Mortgage Backed Securities, Other [Member] Schedule of Goodwill [Table] Schedule of Goodwill [Table] Maximum exposure Concentration Risk, Credit Risk, Financial Instrument, Maximum Exposure market comparable Valuation, Market Approach [Member] Change in net funded status of benefit plans: Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax and Reclassification Adjustment, Attributable to Parent [Abstract] Investment gain realized on transfer Investment Gain (Loss) On Reinsurance Investment Gain (Loss) On Reinsurance Income before income taxes Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Derivative term of contract Derivative, Term of Contract Compensation deduction limitation Effective Tax Rate Reconciliation, Nondeductible Expense, Compensation Deduction Limitation, Amount Effective Tax Rate Reconciliation, Nondeductible Expense, Compensation Deduction Limitation, Amount 2014 Short-duration Insurance Contracts, Accident Year 2014 [Member] Insurance Premiums and Contract Charges Earned Insurance Premiums Revenue Recognition, Policy [Policy Text Block] Weighted Average Option Price per Share, Beginning Balance (in usd per share) Weighted Average Option Price per Share, Ending Balance (in usd per share) Total Outstanding Options, Weighted Average Option Price per Share (in usd per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price Acquisition of treasury stock Payments for Repurchase of Equity Acquisition of businesses, net of cash acquired Acquisition of businesses Payments to Acquire Businesses, Net of Cash Acquired Common stock, shares authorized (in shares) Common Stock, Shares Authorized Summary of changes in outstanding restricted common stock units Share-based Payment Arrangement, Restricted Stock Unit, Activity [Table Text Block] Premium receivables Increase (Decrease) in Premiums Receivable Property and equipment Property, Plant and Equipment, Gross Proceeds from exercise of stock options Proceeds from Stock Options Exercised 2022 Defined Benefit Plan, Expected Future Benefit Payment, Year Two Change in deposit asset on reinsurance Decrease (Increase) In Reinsurance Deposits, Financing Activities Decrease (Increase) In Reinsurance Deposits, Financing Activities Summarized financial information for these segments Schedule of Segment Reporting Information, by Segment [Table Text Block] Funded status Defined Benefit Plan, Funded (Unfunded) Status of Plan Goodwill Goodwill and Intangible Assets, Goodwill, Policy [Policy Text Block] Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] Income Statement [Abstract] Income Statement [Abstract] Accumulated other comprehensive income (loss), net of tax: Total AOCI Attributable to Parent [Member] Distribution of the company's fixed maturity portfolio by estimated expected maturity Investments Classified by Contractual Maturity Date [Table Text Block] Unallocated claims adjustment expenses Short-duration Insurance Contracts, Liability for Unpaid Claims and Claims Adjustment Expense, Accumulated Unallocated Claim Adjustment Expense Schedule of Segment Reporting Information, by Segment [Table] Schedule of Segment Reporting Information, by Segment [Table] Summary of options outstanding segregated by ranges of exercise prices Share Based Compensation Stock Option Activities By Exercise Range [Abstract] Purchases Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Purchases Property and Casualty segment Property, Liability and Casualty Insurance Product Line [Member] Separate Account (Variable Annuity) Assets and Liabilities Policyholder Accounts, Policy [Policy Text Block] Use of Estimates Use of Estimates, Policy [Policy Text Block] Discount percent on issuance Debt Instrument Percentage Of Discount On Issuance Debt instrument percentage of discount on issuance. Adjustment for performance achievement, Weighted Average Grant Date Fair Value per Unit (in usd per share) Share based Compensation Arrangement By Share based Payment Award Equity Instruments Other Than Options Granted Vested In Period Weighted Average Adjustment For Performance Achievement Date Fair Value Share based Compensation Arrangement By Share based Payment Award Equity Instruments Other Than Options Granted Vested In Period Weighted Average Adjustment For Performance Achievement Date Fair Value Non-redeemable preferred stocks Nonredeemable Preferred Stock [Member] Consolidated Entities [Axis] Consolidated Entities [Axis] Premium revenue/ premium earned SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Premium Revenue Amount life catastrophe risk retention per occurrence Amount Life Catastrophe Risk Retention Per Occurrence Amount life catastrophe risk retention per occurrence. State licenses License [Member] Number of operating lease not yet commenced Lessee, Operating Lease, Not Yet Commenced, Number Lessee, Operating Lease, Not Yet Commenced, Number Net investment gains (losses) Total Net investment gains (losses) Realized Investment Gains (Losses) Counterparty Name [Domain] Counterparty Name [Domain] Consolidation Items [Domain] Consolidation Items [Domain] Schedule of Gain (Loss) on Securities [Table] Schedule of Gain (Loss) on Securities [Table] Prior year adjustments Effective Income Tax Rate Reconciliation, Prior Year Income Taxes, Amount Forfeited, Vested, Units (in shares) Share based Compensation Arrangement By Share based Payment Award Equity Instruments Other Than Options Forfeited Forfeited In Period Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeited In Period Deferred policy acquisition costs, corridor around the mean Deferred Policy Acquisition Costs, Corridor Around The Mean Deferred Policy Acquisition Costs, Corridor Around The Mean Condensed Financial Statements [Table] Condensed Financial Statements [Table] Goodwill and Intangible Assets, net Goodwill and Intangible Assets Disclosure [Text Block] Available-for-sale securities, allowance for credit losses Debt Securities, Available-for-sale, Allowance for Credit Loss Actual return on plan assets Defined Benefit Plan, Plan Assets, Increase (Decrease) for Actual Return (Loss) Fixed maturity securities, Gross Unrealized Losses, Total Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss Summary of reinsurance recoverable on unpaid insurance reserves Summary of reinsurance recoverable on unpaid insurance reserves [Abstract] Short-duration Insurance Contracts, Accident Year [Axis] Short-duration Insurance Contracts, Accident Year [Axis] DAC unlocking and amortization expense Deferred Policy Acquisition Costs, Amortization Expense Maturing On January 12, 2024 Maturing On January 12 2024 [Member] Maturing On January 12 2024 [Member] Loss before income tax benefit and equity in net earnings of subsidiaries Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest Limited partnership interests Payments For Proceeds From Limited Partnership Investments [Abstract] Payments For Proceeds From Limited Partnership Investments [Abstract] 2026-2030 Defined Benefit Plan, Expected Future Benefit Payment, after Year Five for Next Five Years Operating Lease, Liability, Statement of Financial Position [Extensible List] Operating Lease, Liability, Statement of Financial Position [Extensible List] Impaired securities Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Impairment Losses Equity securities at fair value Equity Securities, FV-NI Entity [Domain] Entity [Domain] Withholding tax payments on RSUs tendered Payment, Tax Withholding, Share-based Payment Arrangement Acquisitions Goodwill, Acquired During Period Fair Value SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties, Fair Value Unaudited Selected Quarterly Financial Data Quarterly Financial Information [Text Block] Assumed from Other Companies Assumed Premiums Earned Less: reclassification adjustment for net investment gains (losses) included in income before income tax Reclassification adjustment for net investment gains (losses) included in income before income tax Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, before Tax Property, plant and equipment, useful life Property, Plant and Equipment, Useful Life Goodwill [Line Items] Goodwill [Line Items] Lessee, Lease, Description [Line Items] Lessee, Lease, Description [Line Items] Amount of group life policy insurance risk retained Amount Of Group Life Policy Insurance Risk Retained Amount of maximum group life policy insurance risk retained. Fair Value Disclosures [Abstract] Fair Value Disclosures [Abstract] Total Debt and Lease Obligation Year Six Short-duration Insurance Contracts, Historical Claims Duration, Year Six Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward] Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward] Fixed maturity securities, available for sale, at fair value (amortized cost 2020, $5,788,551; 2019, $5,456,980) Fair Value Total Fair value of issued securities Debt Securities, Available-for-sale Add (deduct) tax effects of: Effective Income Tax Rate Reconciliation, Other Reconciling Items, Amount [Abstract] Retirement Retirement annuity [Member] Deferred Policy Acquisition Costs Deferred Charges, Policy [Policy Text Block] Minimum funding requirement Defined Benefit Plan and Other Post Retirement Plan Minimum Funding Required Defined benefit plan and other post retirement plan minimum funding required. Range of Option Prices per Share Share-based Payment Arrangement, Option, Exercise Price Range, Beginning of Period [Abstract] Consolidated Entities [Domain] Consolidated Entities [Domain] Mortgage-backed securities Government mortgage-backed securities Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] equity value Measurement Input Equity Value [Member] Measurement Input Equity Value Investment contract reserves Liability for Future Policy Benefits, Individual and Group Annuities and Supplementary Contracts Derivative instruments, gain (loss) Derivative Instruments, Gain (Loss) [Table Text Block] Forfeited, Total Outstanding, Weighted Average Grant Date Fair Value per Unit (in usd per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value Stock options fair value pricing model weighted-average assumptions Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block] Percentage of employer match Defined Contribution Plan, Employer Matching Contribution, Percent of Match Schedule of derivative instruments in statement of financial position, fair value Schedule of Derivative Instruments in Statement of Financial Position, Fair Value [Table Text Block] Granted, Weighted Average Grant Date Fair Value per Unit (in usd per share) Share based Compensation Arrangement By Share based Payment Award Equity Instruments Other Than Options Granted Vested In Period Weighted Average Grant Date Fair value Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Granted Vested In Period Weighted Average Grant Date Fair Value. Fair Value of Financial Instruments Fair Value Disclosures [Text Block] 2015 Short-duration Insurance Contracts, Accident Year 2015 [Member] Settlements Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements Current year Liability for Unpaid Claims and Claims Adjustment Expense, Claims Paid, Current Year Amortization term for acquisition costs of indexed universal life contracts Acquisition Costs Amortization In Years For Indexed Universal Life Contracts The number of years over which capitalized acquisition costs are amortized for indexed universal life contracts. Acquisition costs are amortized in proportion to estimated gross profits. Derivatives, Fair Value [Line Items] Derivatives, Fair Value [Line Items] Cumulative effect of change in accounting principle Cumulative Effect, Period of Adoption, Adjustment [Member] Additional paid-in capital Additional paid-in capital Additional Paid in Capital, Common Stock Entity Registrant Name Entity Registrant Name Summary of options outstanding segregated by ranges of exercise prices Share Based Compensation Stock Option Outstanding By Exercise Range [Table Text Block] A table of share based compensation stock option outstanding by exercise range, shown as a text block. Weighted average discount rate Operating Lease, Weighted Average Discount Rate, Percent Claims and claim expense payments for claims occurring during: Liability for Unpaid Claims and Claims Adjustment Expense, Claims Paid [Abstract] Financial Assets Assets, Fair Value Disclosure [Abstract] Potential variability of property and casualty loss reserves Potential Variability Of Property and Casualty Loss Reserves Potential percentage variability (plus or minus) of property and casualty loss reserves within a reasonable probability of other possible outcomes. Intersegment eliminations Intersegment Eliminations [Member] Beginning balance, Vested, Units (in shares) Ending balance, Vested, Units (in shares) Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested Number Share based compensation arrangement by share based payment award equity instruments other than options vested number. Amortization period of acquisition costs of interest sensitive life contracts Amortization Period Of Acquisition Costs Related To Interest Sensitive Life Contracts The number of years over which capitalized acquisition costs are amortized on interest sensitive life contracts. Capitalized acquisition costs are amortized in proportion to estimated gross profits. Options Vested and Exercisable, Granted (in shares) Share based Compensation Arrangement By Share based Payment Award Options Vested And Exercisable Granted In Period Share Based Compensation Arrangement By Share Based Payment Award Options Vested And Exercisable Granted In Period. Weighted Average Option Price per Share Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract] Principal repayment on FHLB funding agreements Payments of FHLBank Borrowings, Financing Activities Banking & finance and insurance companies Banks, Trust and Insurance, Equities [Member] Dividends paid to shareholders Payments of Ordinary Dividends, Common Stock SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items] SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items] Equity securities Equity Securities [Member] Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Investments Investments Investments [Abstract] Other policyholder funds, embedded derivatives Other Policyholder Funds Derivative Instruments Fair Value Disclosure Fair value of the liability as of the policyholders for funds held that are returnable under the terms of insurance contracts that were not separately reported. Due after 10 years through 20 years Due after 10 years through 20 years, Percent of Total Fair Value Percentage of fair value of available for sale debt securities maturing in the eleventh rolling twelve months through the twentieth rolling twelve months following the latest balance sheet presented. Income tax (asset) liability Income tax asset liability [Abstract] Net unrealized investment gains on fixed maturity securities Net unrealized investment gains on fixed maturity securities AOCI, Debt Securities, Available-for-sale, Adjustment, after Tax Premiums written SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Premium Written Retention base amount per occurrence under layer three Retention Base Amount Per Occurrence Under Layer Three Retention base amount per occurrence under layer three. Unrealized Losses Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax Remaining lease term Lessee, Operating Lease, Remaining Lease Term Entity Address, Postal Zip Code Entity Address, Postal Zip Code Components of comprehensive income Comprehensive Income (Loss) [Table Text Block] Discounting of unpaid claims and claim expense tax reserves (transitional rule) Deferred Tax Liabilities, Tax Deferred Expense, Reserves and Accruals, Loss Reserves, Transitional Rule Deferred Tax Liabilities, Tax Deferred Expense, Reserves and Accruals, Loss Reserves, Transitional Rule Goodwill Beginning balance Ending balance Goodwill Debt Securities, Available-for-sale [Line Items] Debt Securities, Available-for-sale [Line Items] Fair value measurement inputs and valuation techniques Fair Value Measurement Inputs and Valuation Techniques [Table Text Block] Other comprehensive income (loss) Net current period other comprehensive income (loss) Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent Life Life Life and Health [Member] Net operating loss carryforwards Deferred Tax Assets, Operating Loss Carryforwards Investment expenses Investment Income, Investment Expense Range of Option Prices per Share, Expired (in usd per share) Share Based Compensation Shares Expired Under Stock Option Plans Exercise Price Range Share based compensation shares expired under stock option plans exercise price range. Principal amount Debt Instrument, Face Amount Separate Account (variable annuity) assets Separate account asset Separate Account Asset Maturing On May 17 2021 Maturing On May 17 2021 [Member] Maturing On May 17 2021 Percentage of outstanding shares reacquired Treasury Stock, Percentage of Outstanding Shares Reacquired Treasury Stock, Percentage of Outstanding Shares Reacquired Schedule of goodwill Schedule of Goodwill [Table Text Block] Percentage of Amount Assumed to Net SEC Schedule, 12-17, Insurance Companies, Reinsurance, Premium, Percentage Assumed to Net Options Outstanding, Forfeited (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period Investment Holdings [Line Items] Investment Holdings [Line Items] Equity [Abstract] Equity [Abstract] Acquisitions Indefinite-lived Intangible Assets Acquired Accounting Standards Update [Extensible List] Accounting Standards Update [Extensible List] Short-term and other investments Short-Term And Other Investments Short-Term And Other Investments Transfers out of Level 3 Fair Value, Measurement with Unobservable Inputs Reconciliation, Liability, Transfers out of Level 3 Weighted Average Option Price per Share, Options Granted (in usd per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price Weighted average exercise prices of vested and exercisable options (in usd per share) Vested and Exercisable Options, Weighted Average Option Price per Share (in usd per share) Share Based Compensation Arrangement By Share Based Payment Award Options Vested And Exercisable Weighted Average Exercise Price Share based compensation arrangement by share based payment award options vested and exercisable weighted average exercise price. Reinsurance recoverables, including reinsurance premium paid Reinsurance Recoverable for Unpaid Claims and Claims Adjustments Third Party Reinsurer Risk Customer Concentration Risk [Member] Supplemental balance sheet information related to operating leases Assets And Liabilities, Lessee [Table Text Block] Assets And Liabilities, Lessee Future amortization expense Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block] Derivative Contract [Domain] Derivative Contract [Domain] Due after 1 year through 5 years Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling after One Through Five Years, Fair Value Diluted (in shares) Total common and common equivalent shares adjusted to calculate diluted earnings per share (in shares) Shares of common stock and equivalent shares - weighted average diluted (in shares) Weighted Average Number of Shares Outstanding, Diluted Distributed, Total Outstanding Units (in shares) Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Distributed In Period Share based compensation arrangement by share based payment award equity instruments other than options distributed in period. Automobile physical damage Auto Physical Damage [Member] Number of operating segments Number of Operating Segments haircut Measurement Input Haircut [Member] Measurement Input Haircut Forfeited, Total Outstanding Units (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period Debt Disclosure [Abstract] Debt Disclosure [Abstract] Deposit Asset On Reinsurance Deposit Asset On Reinsurance [Member] Deposit Asset On Reinsurance Percentage of coverage for catastrophe losses above retention amount, layer one Percentage Of Coverage For Catastrophe Losses Above Retention Amount, Scenario One Percentage of coverage for catastrophe losses above retention amount. Insurance premiums and contract charges earned Premiums and contract charges earned, Net Amount Insurance premiums and contract charges earned Premiums and contract charges earned, Net Amount The sum of insurance premiums earned, premiums earned on the income statement for all insurance contracts after subtracting any amounts ceded to another insurer and adding premiums assumed from other insurers, plus contract charges earned on investment and universal life-type contracts. Net cash provided by (used in) financing activities Net Cash Provided by (Used in) Financing Activities Number of hard-to-value fixed maturity securities Number Of Hard To Value Fixed Maturity Securities Number Of Hard To Value Fixed Maturity Securities Benefits, claims and settlement expenses Benefits, claims and settlement expenses Policyholder Benefits and Claims Incurred, Net Fixed maturities Fixed maturities Fixed maturities. Balance as of the beginning of the year Balance as of the end of the year Unrecognized Tax Benefits Counterparty Name [Axis] Counterparty Name [Axis] Common stock, $0.001 par value, authorized 75,000,000 shares; issued, 2020, 66,316,797; 2019, 66,088,808 Common stock, $0.001 par value, authorized 75,000,000 shares; issued, 2020, 66,316,797; 2019, 66,088,808 Common Stock, Value, Issued 2024 Defined Benefit Plan, Expected Future Benefit Payment, Year Four Long-term debt Long-term Debt [Member] Equity in net earnings of subsidiaries Equity in net earnings of subsidiaries Equity In Net Earnings Of Subsidiaries Equity in net earnings of subsidiaries. Finite-Lived Intangible Assets [Line Items] Finite-Lived Intangible Assets [Line Items] Document Fiscal Year Focus Document Fiscal Year Focus Maturing On June 26 2025 Maturing On June 26 2025 [Member] Maturing On June 26 2025 Amortization in 2022 2022 Finite-Lived Intangible Asset, Expected Amortization, Year Two Reinsurance recoverables Increase (Decrease) in Reinsurance Recoverable Projected benefit obligation at beginning of year Projected benefit obligation at end of year Defined Benefit Plan, Benefit Obligation Settlements Unrecognized Tax Benefits, Decrease Resulting from Settlements with Taxing Authorities Net other-than-temporary impairment losses on securities recognized in net income Net other-than-temporary impairment losses on securities recognized in net income Other-than-temporary Impairment Loss, Debt Securities, Portion Recognized in Earnings Entity Current Reporting Status Entity Current Reporting Status Loss before equity in net earnings of subsidiaries Loss Before Equity in Net Income of Consolidated Subsidiaries after Tax Loss before equity in net income of consolidated subsidiaries after tax. Net investment (gains) losses included in net income related to financial liabilities Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Gain (Loss) Included in Earnings Assets Derivative Asset [Abstract] Purchases Payments to Acquire Debt Securities, Available-for-sale Earnings Per Share Earnings Per Share, Policy [Policy Text Block] Coverage above retention per occurrence under layer three catastrophe reinsurance Coverage Above Retention Per Occurrence Under Layer Three Catastrophe Reinsurance Coverage provided above retention per occurrence under layer three of catastrophe excess of loss reinsurance coverage. Other income Other Income Common stock, shares issued (in shares) Common Stock, Shares, Issued Options Vested and Exercisable, Vested (in shares) Share Based Compensation Arrangement By Share Based Payment Award Options Vested And Exercisable Vested In Period Share based compensation arrangement by share based payment award options vested and exercisable vested in period. Operating lease liabilities, included in Other liabilities Total Operating Lease, Liability Net deferred tax liability Deferred Tax Liabilities, Net Segment Reporting [Abstract] Segment Reporting [Abstract] Basis of Presentation and Significant Accounting Policies Basis of Presentation and Significant Accounting Policies [Text Block] December 2, 2022 Maturity Period Two [Member] Maturity Period Two [Member] Debt Instrument [Line Items] Debt Instrument [Line Items] Total shareholders' equity Beginning balance Ending balance Stockholders' equity Stockholders' Equity Attributable to Parent Separate Account (variable annuity) liabilities Separate account liability Separate Account, Liability Value of business acquired Business Combination, Consideration Transferred discounted cash flow Valuation Technique, Discounted Cash Flow [Member] Amortization term for acquisition costs of annuity contracts Acquisition Costs Amortization In Years For Annuity Contracts The number of years over which capitalized acquisition costs are amortized for annuity contracts. Acquisition costs are amortized in proportion to estimated gross profits. Entity Address, City or Town Entity Address, City or Town Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] Restricted stock units Restricted Stock Units (RSUs) [Member] 2025 Lessee, Operating Lease, Liability, to be Paid, Year Five Financial Instrument [Axis] Financial Instrument [Axis] Schedule of short-duration insurance contracts, claims development Short-duration Insurance Contracts, Claims Development [Table Text Block] Due after 10 years through 20 years Due after 10 years through 20 years, Amortized Cost Amount of available-for-sale debt securities at cost, net of adjustments, maturing in the eleventh rolling twelve months through the twentieth rolling twelve months following the latest balance sheet presented. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings (less any cumulative-effect adjustments, as defined) and fair value hedge accounting adjustments. Short-term lease cost Short-term Lease, Cost Indefinite-lived Intangible Assets [Axis] Indefinite-lived Intangible Assets [Axis] Foreign government bonds Foreign Government Debt [Member] Amortization in 2023 2023 Finite-Lived Intangible Asset, Expected Amortization, Year Three Gross gains realized Equity Securities, FV-NI, Realized Gain Probability of other possible outcomes possible impact on net income Probability Of Other Possible Outcomes Possible Impact On Net Income Equated Net Income impact (plus or minus) of potential percentage variability (plus or minus) of property and casualty loss reserves within a reasonable probability of other possible outcomes. Current Current Income Tax Liabilities (Assets) Current income tax assets liabilities. Other short duration lines Other Short Duration Lines [Member] SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information [Line Items] SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information [Line Items] Other tax expense (benefit) Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Tax Leases [Abstract] Leases [Abstract] Benefits, losses and expenses Expenses Benefits, Losses and Expenses [Abstract] Long-term Debt, Type [Axis] Long-term Debt, Type [Axis] Corporate and Other Corporate and Other [Member] Effects of Reinsurance [Table] Effects of Reinsurance [Table] Net income per share Earnings Per Share [Abstract] Schedule II Condensed Financial Information of Registrant Condensed Financial Information of Parent Company Only Disclosure [Text Block] Summary of deferred tax assets and liabilities Schedule of Deferred Tax Assets and Liabilities [Table Text Block] Net Investment Income [Line Items] Net Investment Income [Line Items] Prior service cost Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), Reclassification Adjustment from AOCI, before Tax Net increase (decrease) in cash Cash, Period Increase (Decrease) Net Funded Status of Benefit Plans Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member] Other Payments for Other Operating Activities Pension cost (credit) Pension Cost (Reversal of Cost) FHLB of Chicago Federal Home Loans Bank Of Chicago [Member] Amortization in 2025 2025 Finite-Lived Intangible Asset, Expected Amortization, Year Five Document Fiscal Period Focus Document Fiscal Period Focus Gross Amount SEC Schedule, 12-17, Insurance Companies, Reinsurance, Life Insurance in Force, Gross Consolidated net income, statutory basis Statutory Accounting Practices, Statutory Net Income Amount Contributions to employees' accounts Employer contributions Defined Benefit Plan, Plan Assets, Contributions by Employer Mortgage loans Mortgages [Member] Debt redemption price, percentage Debt Instrument, Redemption Price, Percentage Other Other Long-term Investments [Member] Entity Filer Category Entity Filer Category Common stock Common Stock [Member] Product and Service [Domain] Product and Service [Domain] Net investment gains (losses) Realized Investment Gains (Losses) [Abstract] State insurance facilities Property Liability and Casualty Insurance State Insurance Facilities [Member] NTA National Teachers Associates Life Insurance Company [Member] National Teachers Associates Life Insurance Company [Member] Concentration Risk Benchmark [Domain] Concentration Risk Benchmark [Domain] Bank Credit Facility Short-term Bank Loans and Notes Payable Net Amount SEC Schedule, 12-17, Insurance Companies, Reinsurance, Life Insurance in Force, Net Net investment income SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Net Investment Income Effective Interest Rates Stated rate Debt Instrument, Interest Rate, Stated Percentage Municipal bonds Municipal bonds Municipal Bonds [Member] Insurance lines other than short duration Other Than Short Duration Line [Member] Diluted: Diluted Earnings Per Share, Diluted [Abstract] Free-standing derivatives Free Standing Derivatives [Member] Free Standing Derivatives Member Options Outstanding, Exercised (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period CSUs related to deferred compensation for employees (in shares) Incremental Common Shares Attributable To Common Stock Units Related To Deferred Compensation For Employees Incremental common shares attributable to common stock units related to deferred compensation for employees. 2018 Camp Fire In California 2018 Camp Fire In California [Member] 2018 Camp Fire In California Net (decrease) increase in cash Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect Net unrealized investment gains (losses) on securities arising during the period OCI, Debt Securities, Available-for-Sale, Unrealized Holding Gain (Loss), before Adjustment and Tax Employee stock option Share-based Payment Arrangement, Option [Member] Benefits, claims and settlement expenses, Gross Amount Policyholder Benefits and Claims Incurred, Direct Summary of fair value and gross unrealized losses of fixed maturity securities and equity securities in an unrealized loss position Debt Securities, Available-for-sale [Abstract] Condensed Financial Information Disclosure [Abstract] Condensed Financial Information Disclosure [Abstract] Vested Units Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested, Number of Shares [Roll Forward] Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested, Number of Shares [Roll Forward] Number of position with a gross unrealized loss, Total Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions Treasury stock (in shares) Treasury Stock, Shares Value of agency relationship Value of Agency Relationship Value of Agency Relationship Total other-than-temporary impairment losses on securities Other than Temporary Impairment Losses, Investments Interest sensitive life contracts Interest Sensitive Life Contracts [Member] Expected return on plan assets Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Rate of Return on Plan Assets Restricted net assets of HMEC's insurance subsidiaries Statutory Accounting Practices Restricted Net Assets Statutory accounting practices restricted net assets. Interest Interest Paid, Excluding Capitalized Interest, Operating Activities Year One Short-duration Insurance Contracts, Historical Claims Duration, Year One FHLB interest rate Federal Home Loan Bank, Advances, Branch of FHLB Bank, Interest Rate Amortization of deferred policy acquisition costs SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Amortization of Deferred Policy Acquisition Cost IUL - embedded derivatives, reported in Investment contract and policy reserves Liability For Future Policy Benefits Derivative Instruments Carrying Amount Carrying amount of accrued obligation to policyholders that relates to insured events under other insurance contracts. Amortization in 2021 2021 Finite-Lived Intangible Asset, Expected Amortization, Year One Total revenues Total revenues Revenues Favorable development of total reserves for property and casualty claims occurring in prior years Favorable Development Of Total Reserves For Property And Casualty Claims Occurring In Prior Years The reduction in the estimate of the amount needed to settle claims relating to property and casualty insured events that have occurred in prior years. Claims occurring in the current year Claims and claims adjustment expense incurred related to current year Current Year Claims and Claims Adjustment Expense Financing receivable credit quality indicators Schedule of Derivative Instruments [Table Text Block] Income taxes Income Taxes Paid, Net Impairment charges of intangible assets Impairment of Intangible Assets (Excluding Goodwill) Contributions to employees' accounts Defined Contribution Plan, Employer Discretionary Contribution Amount Adjustment for performance achievement, Weighted Average Grant Date Fair Value per Unit (in usd per share) Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Adjustment For Performance Achievement In Period Weighted Average Grant Date Fair Value Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Adjustment For Performance Achievement In Period Weighted Average Grant Date Fair Value Diluted (in usd per share) Net income per share - diluted (in usd per share) Net income - diluted (in usd per share) Earnings Per Share, Diluted Sales Proceeds from Sale of Debt Securities, Available-for-sale Unrecognized tax benefits, excluding interest and penalties Schedule of Unrecognized Tax Benefits Roll Forward [Table Text Block] Policy loans Policy Loans [Member] Deferred tax liabilities Deferred Tax Liabilities, Net [Abstract] Summary of indebtedness outstanding Schedule of Debt [Table Text Block] Total, net of tax Other Comprehensive Income (Loss), Available-For-Sale Securities Adjustment, Net Of Tax, Portion Attributable To Parent, Before Cumulative Effect Of Change In Accounting Principle Other Comprehensive Income (Loss), Available-For-Sale Securities Adjustment, Net Of Tax, Portion Attributable To Parent, Before Cumulative Effect Of Change In Accounting Principle Eliminations Consolidation, Eliminations [Member] Investment Portfolio Investment Portfolio [Member] Investment Portfolio Entity Address, Address Line One Entity Address, Address Line One Entity Emerging Growth Company Entity Emerging Growth Company SEC Schedule, 12-17, Insurance Companies, Reinsurance [Table] SEC Schedule, 12-17, Insurance Companies, Reinsurance [Table] Beginning balance Ending balance Indefinite-lived Intangible Assets (Excluding Goodwill) Deferred Deferred Income Tax Expense (Benefit) Benefits, claims and settlement expenses, Ceded to Other Companies Policyholder Benefits and Claims Incurred, Ceded Accumulated amortization and impairments: Finite-Lived Intangible Assets, Accumulated Amortization Range Two Exercise Price Range Range Two [Member] Maximum Maximum [Member] Amortization of: Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax [Abstract] Preferred stock, shares authorized (in shares) Preferred stock, shares authorized (in shares) Preferred Stock, Shares Authorized Dividends, 2020, $1.20 per share; 2019, $1.15 per share; 2018, $1.14 per share Dividends, Common Stock, Cash Sales and other, net Debt Securities, Gain (Loss), Excluding OTTI Other Policyholder Funds Other Policy holder Funds [Policy Text Block] Disclosure of accounting policy for funds held that are returnable under terms of insurance contracts that were not separately reported, and amounts payable under Federal Home Loan Bank Funding agreements. Guarantee of premium roll-up at an annual rate of 3% or 5% Variable Annuity Contract Value Distribution Guarantee Of Premium Roll Up Annual Interest Rate Variable annuity contract value distribution guarantee of premium roll up annual interest rate. Incurred claims and claim expenses: Liability for Unpaid Claims and Claims Adjustment Expense, Incurred Claims [Abstract] Capital contributions to subsidiaries Payments of Distributions to Affiliates 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] Proceeds from FHLB funding agreements Proceeds From FHLB Funding Agreements Proceeds From FHLB Funding Agreements Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Percentage of investment portfolio fair value pricing services or index price Percentage Of Investment Portfolio Fair Value Pricing Services Or Index Price Percentage of investment portfolio fair value pricing services or index price. Other Other Nonoperating Expense Investments [Domain] Investments [Domain] All other corporate bonds Other Corporate Bonds [Member] Redeemable preferred stocks Redeemable Preferred Stock [Member] Amount of property recovery related to risk losses Amount Of Property Recovery Related To Risk Losses Amount of property recovery related to risk losses. Trading Symbol Trading Symbol Accumulated Other Comprehensive Income (Loss) [Table] Accumulated Other Comprehensive Income (Loss) [Table] Premiums and contract charges earned, Gross Amount Direct Insurance Premiums And Contract Charges Earned The sum of insurance premiums earned, premiums earned on the income statement for all insurance contracts before subtracting any amounts ceded to another insurer or adding premiums assumed from other insurers, plus contract charges earned on investment and universal life-type contracts. Guarantee Minimum Death Benefit Guaranteed Minimum Death Benefit [Member] Unearned premium reserve reduction Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Unearned Premiums Reserve Total policy liabilities Total policy liabilities The aggregate amount of policy reserves (provided for future obligations including unpaid claims and claims adjustment expenses), policy benefits (liability for future policy benefits) and unearned premiums as of the balance sheet date. Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, before Tax, Portion Attributable to Parent [Abstract] Organization, Consolidation and Presentation of Financial Statements [Abstract] Reconciliation of property and casualty unpaid claims and claim expenses Schedule of Liability for Unpaid Claims and Claims Adjustment Expense [Table Text Block] Entity Shell Company Entity Shell Company Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] Fair Value Measurement Inputs and Valuation Techniques [Line Items] Fair Value Measurement Inputs and Valuation Techniques [Line Items] Recurring Fair Value, Recurring [Member] Total Total, Percent of Total Fair Value Available for sale securities debt maturities a percentage of fair value. Net Amount at Risk, by Product and Guarantee [Table] Net Amount at Risk, by Product and Guarantee [Table] Vested and Exercisable Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Exercisable [Roll Forward] Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Exercisable [Roll Forward] Weighted Average Option Price per Share, Options Expired (in usd per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Expirations in Period, Weighted Average Exercise Price Transfers into Level 3 Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3 Entity Public Float Entity Public Float Document Type Document Type ICFR Auditor Attestation Flag ICFR Auditor Attestation Flag SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information [Table] SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information [Table] Number of stock options granted (in shares) Options Outstanding, Granted (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross Treasury stock, at cost Treasury Stock [Member] Unpaid claims and claim expenses Gross reserves, beginning of year Gross reserves, end of year Gross reserves, end of year Liability for Claims and Claims Adjustment Expense Reinsurance Recoverable on Unpaid Insurance Reserves [Line Items] Reinsurance Recoverable on Unpaid Insurance Reserves [Line Items] Schedule of reconciliation of the net incurred and paid claims development tables to the liability for claims and claim adjustment expenses Schedule of Reconciliation of Net Incurred and Paid Claims Development To Liability for Claims and Claim Adjustment Expenses [Table Text Block] Tabular disclosure for reconciliation of the net incurred and paid claims development tables to the liability for claims and claim adjustment expenses. Segments [Axis] Segments [Axis] Assumed from Other Companies SEC Schedule, 12-17, Insurance Companies, Reinsurance, Life Insurance in Force, Assumed Retirement Plans and Other Postretirement Benefits Retirement Benefits [Text Block] Summary of Company's fair value hierarchy measured at recurring basis Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract] Total, before tax Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, before Tax, Portion Attributable to Parent Accumulated other comprehensive income (loss) Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Vested, Total Outstanding, Weighted Average Grant Date Fair Value per Unit (in usd 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 Premiums and contract charges earned, Ceded to Other Companies Ceded Insurance Premiums And Contract Charges Earned Insurance premiums and contract charges assumed and earned by another insurer as a result of reinsurance arrangements. N spread Measurement Input N Spread [Member] Measurement Input N Spread Level 3 Fair Value, Inputs, Level 3 Fair Value, Inputs, Level 3 [Member] Shares reacquired during period (in shares) Stock Repurchased During Period, Shares Benefits paid Defined Benefit Plan, Plan Assets, Benefits Paid Common stock units related to deferred compensation (in shares) Deferred Compensation Arrangement With Individual Shares Outstanding Deferred compensation arrangement with individual shares outstanding. Net Amounts of Assets/ Liabilities Presented in the Consolidated Balance Sheets Derivatives, reported in Short-term and other investments Fair value Derivative Asset Effects of reinsurance on premiums and benefits Effects of Reinsurance [Table Text Block] Fixed maturity securities Fixed Maturities [Member] SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Table] SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Table] Line of Credit Line of Credit [Member] IUL - embedded derivatives, reported in Investment contract and policy reserves Investment Contract and Policy Life Reserves [Member] Investment Contract and Policy Life Reserves [Member] Derivatives Derivative Instruments and Hedging Activities Disclosure [Text Block] Short-term investment funds Short-term Investments Funds [Member] Frozen supplemental defined benefit plans, vesting percentage Frozen Supplemental Defined Benefit Plans, Vesting Percentage Frozen Supplemental Defined Benefit Plans, Vesting Percentage Intangible assets Intangible Assets, Net (Excluding Goodwill) Fixed annuity reserves reinsured on a coinsurance basis Reinsurance Recoverables on Paid Losses, Gross Call option Call Option [Member] Range of Option Prices per Share, Beginning Balance (in usd per share) Range of Option Prices per Share, Ending Balance (in usd per share) Share-based Payment Arrangement, Option, Exercise Price Range, Outstanding, Weighted Average Exercise Price Gross Amounts Not Offset in the Consolidated Balance Sheets, Cash Collateral Received Derivative, Collateral, Obligation to Return Cash Benefits, withdrawals and net transfers to Separate Account (variable annuity) assets Benefits, withdrawals and net transfers to Separate Account (variable annuity) assets The cash outflow for an insurance contract under which the policy holder makes a lump sum payment or a series of payments in exchange for periodic payments to the policyholder beginning immediately or at some future date and net transfer to separate account (variable annuity) assets. T spread Measurement Input T Spread [Member] Measurement Input T Spread Variable Rate [Axis] Variable Rate [Axis] Other investments Other Investments Acquisition of treasury stock Payments for Repurchase of Common Stock Vesting period Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period Thereafter Lessee, Operating Lease, Liability, to be Paid, after Year Five Due after 5 years through 10 years Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling after Five Through Ten Years, Amortized Cost Entity Address, State or Province Entity Address, State or Province Vested, Total Outstanding Units (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period Vested and Exercisable Options, Weighted Average Remaining Term Share Based Compensation Arrangement By Share Based Payment Award Options Vested And Exercisable Weighted Average Remaining Contractual Term Share based compensation arrangement by share based payment award options vested and exercisable weighted average remaining contractual term. Expected federal tax on income Effective Income Tax Rate Reconciliation at Federal Statutory Income Tax Rate, Amount Reinsurance Reinsurance Accounting Policy [Policy Text Block] Range of Option Prices per Share, Exercised (in usd per share) Share Based Compensation Shares Exercised Under Stock Option Plans Exercise Price Range Share based compensation shares exercised under stock option plans exercise price range. Mortality multiplier Measurement Input Mortality Multiplier [Member] Measurement Input Mortality Multiplier Retained earnings Retained earnings Retained Earnings (Accumulated Deficit) Right of use assets, included in Other assets Operating Lease, Right-of-Use Asset Unamortized discount Debt Instrument, Unamortized Discount Deferred policy acquisition costs asset by segment Deferred Policy Acquisition Cost Asset By Segment [Table Text Block] Deferred policy acquisition cost asset by segment. Income taxes Income Taxes Paid Table for reconciliations for all Level 3 assets measured at fair value on a recurring basis Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block] I spread Measurement Input I Spread [Member] Measurement Input I Spread Reinsurance block of in-force fixed and variable annuity business Reinsurance block of in-force fixed and variable annuity business Reinsurance Recoverables, Gross Deferred policy acquisition costs SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Deferred Policy Acquisition Cost Issuances Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Issuances Nonqualified Plan Nonqualified Plan [Member] Equity securities, measurement input Equity Securities, FV-NI, Measurement Input Percentage of invested assets in total investment portfolio Level 3 recurring Percentage Of Invested Assets In Total Investment Portfolio Level3 Recurring Percentage of invested assets in the total investment portfolio in Level 3 carried at fair value on a recurring basis. Amortization of acquisition costs for property and casualty contracts, first term Amortization Period Of Acquisition Costs Related To Property And Casualty Policy Term One The period of time over which capitalized acquisition costs are amortized for property and casualty policies. Acquisition costs are amortized over the term of the insurance policy (6 and 12 months). Income Taxes Income Tax, Policy [Policy Text Block] Total lease cost Lease, Cost Options Vested and Exercisable, Exercisable (in shares) Share Based Compensation Arrangement By Share Based Payment Award Options Vested And Exercisable Exercised In Period Share based compensation arrangement by share based payment award options vested and exercisable exercised in period. 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Investments Investment, Policy [Policy Text Block] Other operating expenses SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Other Operating Expense Homeowners Homeowners [Member] Purchases Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases 2011 Short-duration Insurance Contracts, Accident Year 2011 [Member] Business Acquisition [Axis] Business Acquisition [Axis] Accumulated other comprehensive income (loss), net of tax: Accumulated other comprehensive income (loss), net of taxes: Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract] Interest credited Policyholder Account Balance, Interest Expense Settlement loss Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement Defined Benefit Plan Disclosure [Line Items] Defined Benefit Plan Disclosure [Line Items] Due after 10 years through 20 years Due after 10 years through 20 years, Fair Value Amount of available-for-sale debt securities at fair value maturing in the eleventh rolling twelve months through the twentieth rolling twelve months following the latest balance sheet presented. Fixed income funds Fixed Income Funds [Member] Purchase of FHLB activity-based common stock as percentage of borrowing, percentage, authorized Federal Home Loan Bank, Purchase Of FHLB Activity Based Common Stock, Percentage, Authorized Federal Home Loan Bank, Purchase Of FHLB Activity Based Common Stock, Percentage, Authorized Income tax liabilities Increase (Decrease) in Deferred Income Taxes Year Eight Short-duration Insurance Contracts, Historical Claims Duration, Year Eight Reserves for Fixed Indexed Annuities and Indexed Universal Life Products Interest Expense on Prepetition Liabilities, Policy [Policy Text Block] Proceeds from COVID relief advance Proceeds From COVID Relief Advance Proceeds From COVID Relief Advance Entity Voluntary Filers Entity Voluntary Filers Thereafter Finite-Lived Intangible Asset, Expected Amortization, after Year Five Reinsurance and Catastrophes Reinsurance [Text Block] Credit Facility [Axis] Credit Facility [Axis] Amortization of acquisition costs for individual life contracts, first term Acquisition Costs Amortization In Years For Individual Life Contracts Term One The number of years over which capitalized acquisition costs are amortized for individual life contracts. Acquisition costs are amortized in proportion to the anticipated premiums over the terms of the insurance policies. Preferred stock, shares issued (in shares) Preferred Stock, Shares Issued Weighted average assumptions used to determine benefit obligations as of December 31: Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract] Retirement Plan Tax Status [Domain] Retirement Plan Tax Status [Domain] Net reserves, beginning of year Net reserves, end of year Liability for Unpaid Claims and Claims Adjustment Expense, Net Retirement Plan Name [Domain] Retirement Plan Name [Domain] Total gains or losses Gain Or Loss Net [Abstract] Gain Or Loss Net [Abstract] Limited partnership interests Equity Method Investments [Member] Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Financial Liabilities Financial Liabilities [Abstract] Unamortized debt issuance costs Unamortized Debt Issuance Expense Due after 5 years through 10 years Due after 5 years through 10 years, Percent of Total Fair Value Percentage of fair value of available for sale debt securities maturing in the sixth rolling twelve months through the tenth rolling twelve months following the latest balance sheet presented. Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net Goodwill [Roll Forward] Goodwill [Roll Forward] Proceeds received Proceeds from Sale and Maturity of Debt Securities, Available-for-sale Property and Equipment Property, Plant and Equipment, Net, by Type [Abstract] Computations of net income per share on both basic and diluted bases, including reconciliations of the numerators and denominators Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Reinsurance commissions Deferred Tax Assets, Tax Deferred Expense, Reinsurance Commissions Deferred Tax Assets, Tax Deferred Expense, Reinsurance Commissions Table for reconciliations for all Level 3 assets measured at fair value on a recurring basis Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] Schedule of FHLB funding agreements Schedule Of FHLB Funding Agreements [Table Text Block] Schedule Of FHLB Funding Agreements Senior revolving credit facility Long-term Line of Credit Options Vested and Exercisable, Beginning Balance (in shares) Options Vested and Exercisable, Ending Balance (in shares) Vested and Exercisable Options (in shares) Share Based Compensation Arrangement By Share Based Payment Award Options Vested And Exercisable Outstanding Number Share based compensation arrangement by share based payment award options vested and exercisable outstanding number. Defined Benefit Plan, Plan Assets, Category [Axis] Defined Benefit Plan, Plan Assets, Category [Axis] Net cash provided by operating activities Net Cash Provided by (Used in) Operating Activities Decrease in estimated reserves for claims occurring in prior years Claims and claims adjustment expense incurred related to prior years Prior Year Claims and Claims Adjustment Expense Sales Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Sales Entity Central Index Key Entity Central Index Key Fixed maturity securities, Fair Value Debt Securities, Available-for-sale, Unrealized Loss Position Abstract [Abstract] Debt Securities, Available-for-sale, Unrealized Loss Position Abstract [Abstract] Cumulative effect of change in accounting principle Other Comprehensive Income (Loss), Change In Accounting Principle Adjustment, Net Of Tax Other Comprehensive Income (Loss), Change In Accounting Principle Adjustment, Net Of Tax Derivative Instrument [Axis] Derivative Instrument [Axis] Value of agency relationships Agency Relationships [Member] Agency Relationships [Member] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets by Major Class [Axis] Summary of finite-lived intangible assets Schedule of Finite-Lived Intangible Assets [Table Text Block] 4.50% Senior Notes Senior Notes [Member] Total benefits, losses and expenses Benefits, Losses and Expenses Supplemental Consolidated Cash and Cash Flow Information Cash Flow, Supplemental Disclosures [Text Block] Percentage of life reinsured catastrophe risk in excess specified retention per occurrence amount Percentage of Life Reinsured Catastrophe Risk In Excess Specified Retention Per Occurrence Amount Percentage of life reinsured catastrophe risk in excess specified retention per occurrence amount. Segments [Domain] Segments [Domain] Gross Amount Reinsurance, Gross Amounts [Abstract] Reinsurance, Gross Amounts [Abstract] Short-duration Insurance Contracts, Historical Claims Duration [Line Items] Short-duration Insurance Contracts, Historical Claims Duration [Line Items] Fixed maturities, available for sale, amortized cost Amortized Cost Debt Securities, Available-for-sale, Amortized Cost Unrealized Gains Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax Return of premium guarantee Variable Annuity Contract Value Distribution Return Of Premium Guarantee Percent Variable annuity contract value distribution return of premium guarantee percent. Statement of Cash Flows [Abstract] Statement of Cash Flows [Abstract] Distributed, Vested, Weighted Average Grant Date Fair Value per Unit (in usd per share) Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested Distributed In Period, Weighted Average Grant Date Fair Value Share based compensation arrangement by share based payment award equity instruments other than options vested distributed in period weighted average grant date fair value. 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Due in 1 year or less Due in 1 year or less, Percent of Total Fair Value Percentage of fair value of available for sale debt securities maturing during the next rolling twelve months following the latest balance sheet presented. Other liabilities Other liabilities Other Liabilities Segment Information Segment Reporting Disclosure [Text Block] Variable annuity contract value distribution based on GMDB feature: Variable Annuity Contract Value Distribution Based On Guaranteed Minimum Death Benefit Plan [Abstract] Automobile liability coverage percent reserves Automobile Liability Coverage Percent Reserves Automobile liability coverage reserves as a percentage of total reserves. Defined Benefit Plan, Amounts Recognized in Other Comprehensive Income (Loss) [Abstract] Defined Benefit Plan, Amounts Recognized in Other Comprehensive Income (Loss) [Abstract] Title of 12(b) Security Title of 12(b) Security Fair value as a percentage of total fixed maturities and equity securities fair value, more than 12 months Fair value as percentage of total fixed maturities and equity securities fair value more than 12 months Fair value of positions with a gross unrealized loss for more than twelve months as a percentage of total fixed maturities and equities fair value. Benefits, claims and settlement expenses SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Benefit, Claim, Loss and Settlement Expenses Investment related adjustments Deferred Tax Liabilities, Investments Summary of income tax assets and liabilities Schedule Of Income Tax Assets Liabilities [Table Text Block] Schedule of income tax assets liabilities. Change in fair value - equity securities Equity Securities, FV-NI, Gain (Loss) Total Finite-Lived Intangible Assets, Net Weighted average grant date fair value of stock options granted (in usd per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value Range of Option Prices per Share, Vested (in usd per share) Share Based Compensation Shares Vested Under Stock Option Plans Exercise Price Range Share based compensation shares vested under stock option plans exercise price range. Credit impairment write-downs Other-than-temporary Impairment Loss, Debt Securities, Available-for-sale, Recognized in Earnings Fungible share pool, grant of full value share conversion ratio Fungible Share Pool, Grant Of Full Value Share Conversion Ratio Fungible Share Pool, Grant Of Full Value Share Conversion Ratio Net Amount at Risk by Product and Guarantee [Line Items] Net Amount at Risk by Product and Guarantee [Line Items] 2012 Short-duration Insurance Contracts, Accident Year 2012 [Member] Separate account (variable annuity) assets Schedule of Fair Value of Separate Accounts by Major Category of Investment, Fair Value Weighted Average Option Price per Share, Options Vested (in usd per share) Share Based Compensation Arrangements By Share Based Payment Award Options Vested In Period Weighted Average Exercise Price Share based compensation arrangements by share based payment award options vested in period weighted average exercise price. Less: reinsurance recoverables Plus: reinsurance recoverables Reinsurance recoverables Reinsurance Recoverables, Including Reinsurance Premium Paid Interest expense Interest expense Interest Expense Additional significant financial information for these segments Reconciliation of Other Significant Reconciling Items from Segments to Consolidated [Table Text Block] Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward] Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward] Depreciation and intangible asset amortization Depreciation, Depletion and Amortization Summary of minimum funding requirement and the expected full year contributions for the Company's plans Schedule of Costs of Retirement Plans [Table Text Block] Short-term investments Short-term Investments Short-term Investments [Member] Income taxes expenses Schedule of Components of Income Tax Expense (Benefit) [Table Text Block] Reconciliation of net unrealized investment gains (losses) on fixed maturity securities and equity securities Unrealized Gain (Loss) on Investments [Table Text Block] Options Vested and Exercisable, Expired (in shares) Share Based Compensation Arrangement By Share Based Payment Award Options Vested And Exercisable Expired In Period Share based compensation arrangement by share based payment award options vested and exercisable expired in period. Transfer of investments and policy loans Transfer from Investments Product and Service [Axis] Product and Service [Axis] Amortized Cost Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Amortized Cost, Rolling Maturity [Abstract] Investment Type [Axis] Investment Type [Axis] Change in fair value and gains realized on settlements - derivatives Change in Unrealized Gain (Loss) on Fair Value Hedging Instruments Insurance [Abstract] Insurance [Abstract] Beginning of period End of period Other than Temporary Impairment, Credit Losses Recognized in Earnings, Credit Losses on Debt Securities Held Retirement Plan Tax Status [Axis] Retirement Plan Tax Status [Axis] Supplemental Cash Flow Elements [Abstract] Supplemental Cash Flow Elements [Abstract] Components of net periodic pension (income) expense: Defined Benefit Plan Accumulated Other Comprehensive Income Amortization [Abstract] Liability coverages, Company reinsured each loss above a retention per occurrence Retention Amount Of Each Liability Loss Per Occurrence Retention amount of each liability coverage loss per occurrence. Year Four Short-duration Insurance Contracts, Historical Claims Duration, Year Four Valuation Approach and Technique [Axis] Valuation Approach and Technique [Axis] Coverage above retention per occurrence under layer one catastrophe reinsurance Coverage Above Retention Per Occurrence Under Layer One Catastrophe Reinsurance Coverage provided above retention per occurrence under layer one of catastrophe excess of loss reinsurance coverage. Total Deferred Policy Acquisition Cost, Amortization Expense, Effect of Adjustments to Estimated Gross Profit or Estimated Gross Margin Adjustment for performance achievement, Units (in shares) Share based Compensation Arrangement By Share based Payment Award Equity Instruments Other Than Adjustment For Performance Achievement Options In Period Share based Compensation Arrangement By Share based Payment Award Equity Instruments Other Than Adjustment For Performance Achievement Options In Period Year Seven Short-duration Insurance Contracts, Historical Claims Duration, Year Seven Fair Value, Recurring and Nonrecurring [Table] Fair Value, Recurring and Nonrecurring [Table] Gross Amounts Not Offset in the Consolidated Balance Sheets, Financial Instruments Derivative Asset, Not Offset, Policy Election Deduction Gross gains realized Debt Securities, Available-for-sale, Realized Gain Cash dividends (in usd per share) Common Stock, Dividends, Per Share, Cash Paid Liabilities for claims and claim adjustment expenses, net of reinsurance Short-duration Insurance Contracts, Liability for Unpaid Claims and Allocated Claim Adjustment Expense, Net Maturing On September 11 2025 Maturing On September 11 2025 [Member] Maturing On September 11 2025 Deposit asset on reinsurance Reinsurance Recoverable for Paid Claims and Claims Adjustments Selected quarterly financial data Quarterly Financial Information [Table Text Block] Operating Segments Operating Segments [Member] Acquisition of shares Treasury Stock, Value, Acquired, Cost Method Derivatives embedded in fixed indexed annuity products Derivative Liability Number of positions with a gross unrealized loss, 12 Months or Less Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Number of Positions constant prepayment rate Measurement Input, Constant Prepayment Rate [Member] Dividend received deduction Effective Income Tax Rate Reconciliation, Deduction, Dividends, Amount Change in net unrealized investment gains (losses) on fixed maturity securities Change in net unrealized investment gains (losses) on fixed maturity securities Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax, Portion Attributable to Parent Aggregate in-the-money death benefits under the GMDB provision Aggregate In Money Death Benefits Under Guaranteed Minimum Death Benefit Reserve Provision Aggregate in money death benefits under guaranteed minimum death benefit reserve provision. Total claims and claim expense payments Liability for Unpaid Claims and Claims Adjustment Expense, Claims Paid Expected contract term Fixed Indexed Annuities Term Minimum Fixed indexed annuities term. 401(k) plan Four Zero One K Plan [Member] Other, including consolidating eliminations Insurance, Other [Member] Projected benefit obligation Defined Benefit Plan, Pension Plan with Accumulated Benefit Obligation in Excess of Plan Assets, Projected Benefit Obligation Concentration Risk Type [Axis] Concentration Risk Type [Axis] Proceeds received from sales of fixed maturities and equity securities Schedule of Realized Gain (Loss) [Table Text Block] Supplemental Supplemental Supplemental [Member] Supplemental [Member] Other US Government Debt Securities [Member] New credit losses Other than Temporary Impairment, Credit Losses Recognized in Earnings, Additions, No Previous Impairment Portion of losses recognized in other comprehensive income (loss) Other than Temporary Impairment Losses, Investments, Portion in Other Comprehensive Loss, before Tax, Including Portion Attributable to Noncontrolling Interest Tax-exempt interest Effective Income Tax Rate Reconciliation, Tax Exempt Income, Amount Value of distribution acquired Value Of Distribution Acquired Value Of Distribution Acquired Due after 20 years Due after 20 years, Percent of Total Fair Value Percentage of fair value of available for sale debt securities maturing after the twentieth rolling twelve months following the latest balance sheet presented. Due in 1 year or less Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling within One Year, Amortized Cost 2015 Plan Two Thousand Fifteen Equity Incentive Plan [Member] Fair Value Estimate of Fair Value Measurement [Member] Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net Amortization in 2024 2024 Finite-Lived Intangible Asset, Expected Amortization, Year Four Increases to previously recognized credit losses Other than Temporary Impairment, Credit Losses Recognized in Earnings, Additions, Additional Credit Losses Change in book overdrafts Proceeds from (Repayments of) Bank Overdrafts Acquired finite-lived intangible assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles Total claims and claim expenses incurred Liability for Unpaid Claims and Claims Adjustment Expense, Incurred Claims SEC Schedule, 12-17, Insurance Companies, Reinsurance [Line Items] SEC Schedule, 12-17, Insurance Companies, Reinsurance [Line Items] Cash flows from investing activities Net Cash Provided by (Used in) Investing Activities, Continuing Operations [Abstract] Residential mortgage-backed securities (non-agency) Residential Mortgage Backed Securities [Member] Remaining authorized repurchase amount Stock Repurchase Program, Remaining Authorized Repurchase Amount Equity security funds, International Defined Benefit Plan, Equity Securities, Non-US [Member] Fixed maturity securities, Gross Unrealized Losses Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss [Abstract] Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss [Abstract] NTA NTA Life Enterprises [Member] NTA Life Enterprises [Member] Total Comprehensive Income (Loss), Net of Tax, Attributable to Parent Public utilities Public Utility, Bonds [Member] Expected dividend yield Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate Preferred stock, par value (in usd per share) Preferred Stock, Par or Stated Value Per Share U.S. Government and federally sponsored agency obligations US Government-sponsored Enterprises Debt Securities [Member] Documents Incorporated by Reference Documents Incorporated by Reference [Text Block] Income taxes expenses reconciliation Schedule of Effective Income Tax Rate Reconciliation [Table Text Block] Comprehensive Plan Two Thousand Ten Comprehensive Executive Compensation Plan [Member] Other comprehensive income (loss) before reclassifications OCI, before Reclassifications, Net of Tax, Attributable to Parent 2016 Short-duration Insurance Contracts, Accident Year 2016 [Member] Legal Entity [Axis] Legal Entity [Axis] City Area Code City Area Code Net investment gain (loss) Net investment gains (losses) Embedded Derivative, Gain (Loss) on Embedded Derivative, Net Document Period End Date Document Period End Date Deferred policy acquisition costs Deferred Tax Liabilities, Deferred Expense Year Ten Short-duration Insurance Contracts, Historical Claims Duration, Year Ten Information for pension plans with an accumulated benefit obligation greater than plan assets: Defined Benefit Plan, Plan with Accumulated Benefit Obligation in Excess of Plan Assets [Abstract] Investment contract and life policy reserves Investment Contract And Life Policy Reserves [Table Text Block] A table of investment contract and life policy reserves, shown as a text block. Authorized repurchase amount Stock Repurchase Program, Authorized Amount Sales Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales Number of retirement plans Number Of Retirement Plans Number Of Retirement Plans Quarterly Financial Information Disclosure [Abstract] Quarterly Financial Information Disclosure [Abstract] Shares reacquired during period, value Stock Repurchased During Period, Value Long-term Debt, Type [Domain] Long-term Debt, Type [Domain] Share-based compensation expense Share-based Payment Arrangement, Noncash Expense Policy liabilities Policy liabilities Policy liabilities. Schedule III and VI Supplementary Insurance Information Supplemental Information Concerning Property and Casualty Insurance Operations Supplementary Insurance Information For Insurance Companies Disclosure And Schedule Of Supplemental Information For Property Casualty Insurance Underwriters [Text Block] Supplementary insurance information for insurance companies disclosure and schedule of supplemental information for property casualty insurance underwriters. Dividends received from subsidiaries SEC Schedule, 12-04, Cash Dividends Paid to Registrant, Consolidated Subsidiaries Income tax expense (benefit) Other Comprehensive Income (Loss), Available-for-sale Securities, Tax, Portion Attributable to Parent Sales Proceeds from Limited Partnership Investments Cover [Abstract] Cover [Abstract] Measurement Input Type [Axis] Measurement Input Type [Axis] Prepaid (accrued) benefit expense Defined Benefit Plan Prepaid (Accrued) Benefit Expense Defined benefit plan prepaid (accrued) benefit expense. GNMA Government National Mortgage Association Certificates and Obligations (GNMA) [Member] Employer matching contribution as percent of employees' gross pay Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay Summary of fair value assets and liabilities measured on nonrecurring basis Schedule Of Fair Value Assets And Liabilities Measured On Nonrecurring Basis [Table Text Block] Carrying value, fair value and fair value hierarchy of financial assets and financial liabilities not carried at fair value, are measured on a nonrecurring basis, and fair value disclosure is required. Investment gain realized, net of tax Investment Gain (Loss) On Reinsurance, Net Of Tax Investment Gain (Loss) On Reinsurance, Net Of Tax Fixed maturity securities Fixed income funds Fixed Income Securities [Member] Long-term debt Long-term Debt Operating Leases Lessee, Operating Leases [Text Block] Total other than short duration and unallocated claims adjustment expenses Liability For Other Than Short Duration And Unallocated Claims Adjustment Expenses Liability For Other Than Short Duration And Unallocated Claims Adjustment Expenses Other expenses Defined Benefit Plan Service Cost Other Defined benefit plan service cost other expenses of the plan. Other investments Other Investment [Member] Total investments Investments Retirement Plan Name [Axis] Retirement Plan Name [Axis] Life insurance future policy benefit reserve (transitional rule) Deferred Tax Liabilities, Deferred Expense, Deferred Policy Acquisition Cost, Transitional Rule Deferred Tax Liabilities, Deferred Expense, Deferred Policy Acquisition Cost, Transitional Rule Service cost Defined Benefit Plan, Service Cost Fixed maturity securities Total Debt Securities [Member] Amortization of premiums and accretion of discounts on fixed maturity securities, net Accretion (Amortization) of Discounts and Premiums, Investments Beginning balance Ending balance Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value Concentration Risk Benchmark [Axis] Concentration Risk Benchmark [Axis] Value of customer relationships Customer Relationships [Member] Reclassification of net investment (gains) losses on securities to net income Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Net of Tax Equity Components [Axis] Equity Components [Axis] Range One Exercise Price Range Range One [Member] Due after 1 year through 5 years Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling after One Through Five Years, Amortized Cost Total gross deferred tax assets Deferred Tax Assets, Gross Minimum Minimum [Member] Balance Sheet Location [Domain] Balance Sheet Location [Domain] Barclays Bank PLC Barclays Bank PLC [Member] Unrecognized share-based compensation expense, equity instruments other than options Share-based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount Accumulated benefit obligation Defined Benefit Plan, Plan with Accumulated Benefit Obligation in Excess of Plan Assets, Accumulated Benefit Obligation FHLB advances Federal Home Loan Bank, Advances, Branch of FHLB Bank, Amount of Advances Schedule of supplemental cash flow information related to operating leases Reconciliation of net income to net cash provided by operating activities Schedule of Cash Flow, Supplemental Disclosures [Table Text Block] Defined Benefit Plan, Plan Assets, Category [Domain] Defined Benefit Plan, Plan Assets, Category [Domain] Ceded to Other Companies Ceded Premiums Earned Black-Scholes Valuation Technique Black Scholes [Member] Valuation Technique Black Scholes Asset-backed securities Asset-backed Securities [Member] Actuarial loss Defined Benefit Plan, Amortization of Gain (Loss) Entity Interactive Data Current Entity Interactive Data Current Investments and cash Investments and Cash Net periodic pension expense Defined Benefit Plan, Net Periodic Benefit Cost (Credit) Fair value hierarchy for the Company's defined benefit pension plan assets Schedule of Allocation of Plan Assets [Table Text Block] Weighted Average Option Price per Share, Options Exercised (in usd per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price Compensation accruals Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Employee Compensation Revenues Revenues [Abstract] Cash flows from operating activities Net Cash Provided by (Used in) Operating Activities [Abstract] Summary of changes in outstanding options Share-based Payment Arrangement, Option, Activity [Table Text Block] Summary of fair value and gross unrealized losses of fixed maturity securities and equity securities in an unrealized loss position Debt Securities, Available-for-sale, Unrealized Loss Position, Fair Value [Table Text Block] Maturities, paydowns, calls and redemptions Proceeds from Maturities, Prepayments and Calls of Debt Securities, Available-for-sale Commitment fee percent Line of Credit Facility, Commitment Fee Percentage Share-Based Compensation Share-based Payment Arrangement [Policy Text Block] Health reimbursement account, amount Health Reimbursement Account Balance Health reimbursement account balance. Future policy benefits, claims and claim expenses SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Liability for Future Policy Benefit, Loss, Claim and Loss Expense Due after 20 years Due after 20 years, Amortized Cost Amount of available-for-sale debt securities at cost, net of adjustments, maturing after the twentieth rolling twelve months following the latest balance sheet presented. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings (less any cumulative-effect adjustments, defined) and fair value hedge accounting adjustments. Maturing On December 15, 2023 Maturing On December 15 2023 [Member] Derivative [Table] Derivative [Table] Statement of Stockholders' Equity [Abstract] Statement of Stockholders' Equity [Abstract] 2021 Defined Benefit Plan, Expected Future Benefit Payment, Year One Summary of changes in outstanding options Summary Of Stock Option Activity [Abstract] Total gross deferred tax liabilities Deferred Tax Liabilities, Gross vendor price Vendor Price [Member] Vendor Price Maturity Date [Domain] Maturity Date [Domain] Number of reportable segments Number of Reportable Segments Cost SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties, Cost Value of customer relationship Value of Customer Relationship Value of Customer Relationship Retirement Plan Type [Domain] Retirement Plan Type [Domain] SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Abstract] SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Abstract] Exercise Price Range [Axis] Exercise Price Range [Axis] Net investment income Total net investment income Net Investment Income Effective interest percentage Debt Instrument, Interest Rate, Effective Percentage Consolidation Items [Axis] Consolidation Items [Axis] Weighted average number of common equivalent shares to reflect the dilutive effect of common stock equivalent securities Incremental Weighted Average Shares Attributable to Dilutive Effect [Abstract] Other policyholder funds Other Policyholder Fund The liability as of the balance sheet date for funds held that are returnable under terms of insurance contracts that were not separately reported, and amounts payable under Federal Home Loan Bank Funding agreements. Net actuarial loss (gain) Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss) Arising During Period, before Tax Goodwill impairment Impairments Goodwill, Impairment Loss Assumed from Other Companies Reinsurance, Assumed from Other Companies [Abstract] Reinsurance, Assumed from Other Companies [Abstract] Net funded status of benefit plans Net funded status of benefit plans Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax Total future minimum lease payments Lessee, Operating Lease, Liability, to be Paid RSUs related to incentive compensation (in shares) Incremental Common Shares Attributable To Restricted Common Stock Units Related To Incentive Compensation Incremental common shares attributable to restricted common stock units related to incentive compensation. Retention amount per occurrence related to catastrophe losses, layer one Retention Amount Per Occurrence Related To Catastrophe Losses, Scenario One Retention amount per occurrence related to catastrophe losses. Deferred policy acquisition costs Deferred Policy Acquisition Cost Short-term debt Short-term Debt, Fair Value Benefit Consultants Group Inc. Benefit Consultants Group Inc. [Member] Benefit Consultants Group Inc. [Member] Guaranteed Insurance Contract, Type of Benefit [Axis] Guaranteed Insurance Contract, Type of Benefit [Axis] Range of Option Prices per Share, Granted (in usd per share) Share Based Compensation Shares Granted Under Stock Option Plans Exercise Price Range Share based compensation shares granted under stock option plans exercise price range. Fixed maturity securities Debt Securities, Held-to-maturity, Maturity [Abstract] Cash Cash at beginning of period Cash at end of period Cash Fair Value Measurement Inputs and Valuation Techniques [Table] Fair Value Measurement Inputs and Valuation Techniques [Table] Summary of reinsurance recoverable on unpaid insurance reserves Schedule Of Reinsurance Recoverable On Reserves [Table Text Block] Schedule of reinsurance recoverable on reserves. Summary of cumulative credit losses Other than Temporary Impairment, Credit Losses Recognized in Earnings [Table Text Block] Derivatives Derivative instruments [Member] Effects of Reinsurance [Line Items] Effects of Reinsurance [Line Items] S B L interest margin Measurement Input S B L Interest Margin [Member] Measurement Input S B L Interest Margin Fair value as a percentage of total fixed maturities and equity securities fair value, Total Fair value as percentage of total fixed maturities and equity securities fair value, Total Fair value of positions with a gross unrealized loss as a percentage of total fixed maturities and equities fair value. Document Transition Report Document Transition Report Fixed maturity securities, Gross Unrealized Losses, More than 12 Months Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss Gross Amounts Derivative Asset, Fair Value, Gross Asset Summary of stock units and stock options outstanding under the comprehensive Plan Share Based Compensation Arrangement By Share Based Payment Awards Equity Instruments Outstanding [Table Text Block] A table of share based compensation arrangement by share based payment awards equity instruments outstanding, shown as a text block. Level 2 Fair Value, Inputs, Level 2 [Member] Prior years paid Insurance lines other than short duration Short-duration Insurance Contracts, Liability for Unpaid Claims and Claim Adjustment Expense, Other Reconciling Item Prior years Liability for Unpaid Claims and Claims Adjustment Expense, Claims Paid, Prior Years Financial Liabilities Liabilities, Fair Value Disclosure [Abstract] Vested Units, Weighted Average Grant Date Fair Value per Unit Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested, Weighted Average Grant Date Fair Value [Roll Forward] Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested, Weighted Average Grant Date Fair Value [Roll Forward] Discounting of unpaid claims and claim expense tax reserves Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Loss Reserves Other liabilities Other Liabilities [Member] Cumulative Effect, Period of Adoption [Axis] Cumulative Effect, Period of Adoption [Axis] Unearned premiums SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Unearned Premium Credit Facility [Domain] Credit Facility [Domain] Cumulative credit loss Other than Temporary Impairment, Credit Losses Recognized in Earnings [Roll Forward] Basic (in usd per share) Net income per share - basic (in usd per share) Net income - basic (in usd per share) Earnings Per Share, Basic FHLMC Federal Home Loan Mortgage Corporation Certificates and Obligations (FHLMC) [Member] Equity securities Payments For (Proceeds From) Available-for-sale Securities, Equity Securities [Abstract] Payments For (Proceeds From) Available-for-sale Securities, Equity Securities [Abstract] Schedule of Indefinite-Lived Intangible Assets [Table] Schedule of Indefinite-Lived Intangible Assets [Table] Expected life, in years Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term Entity File Number Entity File Number Options Outstanding, Expired (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Expirations in Period Other policyholder funds Other Policyholder Funds, Fair Value Disclosure Fair Value of the liability as of the balance sheet date to the policyholders for funds held that are returnable under the terms of insurance contracts that were not separately reported. Weighted average remaining lease term Operating Lease, Weighted Average Remaining Lease Term Net Amount Derivative Asset, Fair Value, Offset Against Collateral, Net of Not Subject to Master Netting Arrangement, Policy Election Asset derivatives Offsetting Derivative Assets [Abstract] Supplemental Defined Benefit Plans Supplemental Employee Retirement Plan [Member] FIA - embedded derivatives, reported in Other policyholder funds Other Policyholder Funds Derivative Instruments Carrying Amount Carrying amount liability as of the policyholders for funds held that are returnable under the terms of insurance contracts that were not separately reported. Total amount recognized in Consolidated Balance Sheets, all in Other liabilities Defined Benefit Plan, Amounts for Asset (Liability) Recognized in Statement of Financial Position Investment grade rating Investment Grade Rate Percentage of fair value of fixed maturity and equity securities with a gross unrealized loss having an investment grade rating at period end. Cash flows from operating activities Net Cash Provided by (Used in) Operating Activities, Continuing Operations [Abstract] Adjustment to amortization expenses Adjustment To Amortization Expenses [Table Text Block] Adjustment to amortization expenses. Credit Suisse International Credit Suisse International [Member] Investment Holdings [Table] Investment Holdings [Table] FIA - embedded derivatives, reported in Other policyholder funds Other Policyholder Funds [Member] Other Policyholder Funds [Member] Prior service cost Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, Prior Service Cost (Credit), before Tax Aggregate intrinsic value of vested options Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Aggregate Intrinsic Value Percentage of losses incurred Percentage of Losses Incurred The percentage of losses represented by auto liability and auto physical damage. Share-based compensation expense Share-based Payment Arrangement, Expense Net unrealized investment gains (losses) on securities AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-sale, Parent [Member] Year Five Short-duration Insurance Contracts, Historical Claims Duration, Year Five Balance Sheet Location [Axis] Balance Sheet Location [Axis] Maturing On January 16, 2026 Maturing On January 16 2026 [Member] Weighted average number of shares and equivalent shares Earnings Per Share, Basic and Diluted, Other Disclosures [Abstract] Value of business acquired Business Acquired [Member] Business Acquired [Member] lapse rate Measurement Input Lapse [Member] Measurement Input Lapse Goodwill and Intangible Assets Disclosure [Abstract] Goodwill and Intangible Assets Disclosure [Abstract] Impairment of finite lived intangible assets Impairment of Intangible Assets, Finite-lived Other comprehensive income - net unrealized gains on securities Deferred Tax Liabilities Investments Net Unrealized Gains on Fixed Maturities and Equity Securities Deferred tax liabilities investments net unrealized gains on fixed maturities and equity securities. Document Annual Report Document Annual Report Short-term debt Short-term Debt [Abstract] Reinsurance Contract Modified Coinsurance Basis Reinsurance Contract Modified Coinsurance Basis [Member] Reinsurance Contract Modified Coinsurance Basis [Member] Retirement Benefits [Abstract] Retirement Benefits [Abstract] Governmental agencies as required by law in various states Governmental Agencies as Required by Law in Various States [Member] Estimated expected maturity: Estimated expected maturity: Estimated expected maturity. Schedule of Long-term Debt Instruments [Table] Schedule of Long-term Debt Instruments [Table] Granted, Total Outstanding, Weighted Average Grant Date Fair Value per Unit (in usd per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value Federal Home Loan Bank borrowing Federal Home Loan Bank Advances [Member] Short-term debt Short-term Debt Cash flows from investing activities Net Cash Provided by (Used in) Investing Activities [Abstract] Purchase of FHLB activity-based common stock as percentage of borrowing, required Federal Home Loan Bank, Purchase Of FHLB Activity Based Common Stock As Percentage Of Borrowing, Required Federal Home Loan Bank, Purchase Of FHLB Activity Based Common Stock As Percentage Of Borrowing, Required Discount, if any, deducted in previous column SEC Schedule, 12-18, Supplemental Information, Property-Casualty Insurance Underwriters, Discount Deducted from Reserve Due in 1 year or less Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling within One Year, Fair Value Other, net Deferred Tax Liabilities, Other Schedule of Defined Benefit Plans Disclosures [Table] Schedule of Defined Benefit Plans Disclosures [Table] Investment contract and life policy reserves, embedded derivatives Liability For Future Policy Benefits Derivative Instruments Fair Value Disclosure Fair value disclosure of accrued obligation to policyholders that relates to insured events under other insurance contracts. Gross Amounts Offset in the Consolidated Balance Sheets Derivative Asset, Fair Value, Gross Liability Maturity Date [Axis] Maturity Date [Axis] Statement of Comprehensive Income [Abstract] Statement of Comprehensive Income [Abstract] Concentration Risk Type [Domain] Concentration Risk Type [Domain] Purchases Payments to Acquire Limited Partnership Interests Retention amount of each property loss per occurrence Retention Amount Of Each Property Loss Per Occurrence Retention amount of each property coverage loss per occurrence. 2018 Short-duration Insurance Contracts, Accident Year 2018 [Member] Plan amendments Defined Benefit Plan, Benefit Obligation, Increase (Decrease) for Plan Amendment Total liabilities and shareholders' equity Liabilities and Equity Income Taxes Income Tax Disclosure [Text Block] Portion at Fair Value Measurement Portion at Fair Value Measurement [Member] No guarantee Variable Annuity Contract Value Distribution No Guarantee Percent Variable annuity contract value distribution no guarantee percent. Operating lease cost Operating Lease, Cost Lapse of statute Unrecognized Tax Benefits, Reduction Resulting from Lapse of Applicable Statute of Limitations Other, including U.S. Treasury securities Other, including U.S. Treasury Securities [Member] Other including U.S treasury securities. Catastrophic Event [Domain] Catastrophic Event [Domain] Antidilutive securities exclude from EPS computation (in shares) Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Short-duration Insurance Contracts, Historical Claims Duration [Table] Short-duration Insurance Contracts, Historical Claims Duration [Table] Current Current Income Tax Expense (Benefit) Increases related to current year tax positions Unrecognized Tax Benefits, Increase Resulting from Current Period Tax Positions Increases related to prior year tax positions Unrecognized Tax Benefits, Increase Resulting from Prior Period Tax Positions Useful life (in years) Finite-Lived Intangible Asset, Useful Life Equity Component [Domain] Equity Component [Domain] Change in net unrealized investment gains (losses) on fixed maturity securities OCI, Debt Securities, Available-for-Sale, Gain (Loss), after Adjustment and Tax Postretirement benefits other than pensions Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Postretirement Benefits Insurance Loss Reserves [Abstract] Insurance Loss Reserves [Abstract] Estimated future benefit payments Schedule of Expected Benefit Payments [Table Text Block] Total Property, Plant and Equipment, Net Fair value of collateral Derivative Asset, Fair Value of Collateral Entity Tax Identification Number Entity Tax Identification Number Range Three Exercise Price Range Range Three [Member] Lessee, Lease, Description [Table] Lessee, Lease, Description [Table] Net income Net income Net income Net Income (Loss) Attributable to Parent Changes in: Increase (Decrease) in Operating Capital [Abstract] Average option-adjusted duration, in years Average option-adjusted duration, in years Investment debt securities average option adjusted duration expressed in number of years. Amortization of acquisition costs for individual life contracts, third term Acquisition Costs Amortization In Years For Individual Life Contracts Term Three The number of years over which capitalized acquisition costs are amortized for individual life contracts. Acquisition costs are amortized in proportion to the anticipated premiums over the terms of the insurance policies. London Interbank Offered Rate (LIBOR) London Interbank Offered Rate (LIBOR) [Member] Investment Contract and Life Policy Reserves Liability for Future Policy Benefit [Policy Text Block] Trade names Trade Names [Member] Reinsurance Recoverable On Unpaid Insurance Reserves [Table] Reinsurance Recoverable On Unpaid Insurance Reserves [Table] Current Fiscal Year End Date Current Fiscal Year End Date Statutory surplus and subsidiary dividend restrictions Statutory Accounting Practices Disclosure [Table Text Block] Conversion of restricted common stock units Stock Issued During Period, Value, Conversion Of Restricted Stock Units Value of the stock issued during the period as a result of the conversion of restricted stock units which represented share based compensation. Before tax Other Comprehensive (Income) Loss, Defined Benefit Plan, before Tax, after Reclassification Adjustment, Attributable to Parent Schedule of average annual percentage payout of incurred claims by age, also referred to as a history of claims duration Short-duration Insurance Contracts, Schedule of Historical Claims Duration [Table Text Block] Real estate property Real Estate Property [Member] October 5, 2022 Maturity Period One [Member] Maturity Period One [Member] Accumulated Other Comprehensive Income (Loss) [Line Items] Accumulated Other Comprehensive Income (Loss) [Line Items] Vested, Vested, Units (in shares) Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested Vested In Period Share based compensation arrangement by share based payment award equity instruments other than options vested in period. Outstanding Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward] Other expense - goodwill and intangible asset impairments Other expense - goodwill and intangible asset impairments Goodwill and Intangible Asset Impairment Deposit Asset on Reinsurance Reinsurance Deposit Receivable [Text Block] Reinsurance Deposit Receivable [Text Block] Year Three Short-duration Insurance Contracts, Historical Claims Duration, Year Three Parent company Parent Company [Member] Change in net funded status of benefit plans Change in net funded status of benefit plans Total, net of tax Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax and Reclassification Adjustment, Attributable to Parent Due after 20 years Due after 20 years, Fair Value Amount of available-for-sale debt securities at fair value maturing after the twentieth rolling twelve months following the latest balance sheet presented. Percentage of reversion to mean approach utilized to amortized policy acquisition costs Percentage Of Reversion To Mean Approach Utilized To Amortize Policy Acquisition Costs For the variable deposit portion of the annuity segment, percentage of reversion to the mean approach utilized to amortize policy acquisition costs. Business Acquisition, Acquiree [Domain] Business Acquisition, Acquiree [Domain] Transfers into Level 3 Fair Value, Measurement with Unobservable Inputs Reconciliation, Liability, Transfers Into Level 3 Change in intent write-downs Other than Temporary Impairment Loss, Investments, Portion Recognized In Earnings, Change In Intent Other than Temporary Impairment Loss, Investments, Portion Recognized In Earnings, Change In Intent Equity security funds, United States Defined Benefit Plan, Equity Securities, US [Member] Total (in shares) Share Based Compensation Arrangement By Share Based Payment Awards Equity Instruments Outstanding Share based compensation arrangement by share based payment awards equity instruments outstanding. Property, Plant and Equipment, Type [Domain] Long-Lived Tangible Asset [Domain] FHLB advances Long-term Federal Home Loan Bank Advances Benefits paid Defined Benefit Plan, Benefit Obligation, Benefits Paid Net unrealized investment gains (losses) included in OCI Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Gain (Loss) Included in Other Comprehensive Income (Loss) Property and equipment Property, Plant and Equipment [Table Text Block] Expected contributions (approximations) Defined Benefit Plan and Other Post Retirement Plan Expected Contribution for Next Fiscal Year End Defined benefit plan and other post retirement plan expected contributions for the full next fiscal year as of the current fiscal year-end. Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims Short-duration Insurance Contracts, Incurred But Not Reported (IBNR) Claims Liability Plus Expected Development On Reported Claims, Net Short-duration Insurance Contracts, Incurred But Not Reported (IBNR) Claims Liability Plus Expected Development On Reported Claims, Net Total gains or losses Gain Or Losses Net [Abstract] Gain Or Losses Net [Abstract] At inception: Finite-Lived Intangible Assets, Gross Total amount recognized in AOCI Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, before Tax Cumulative Number of Reported Claims Short-duration Insurance Contract, Cumulative Number of Reported Claims Due after 5 years through 10 years Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling after Five Through Ten Years, Fair Value Fixed maturity securities, Gross Unrealized Losses, 12 Months or Less Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss Summary of Investments-Other Than Investments in Related Parties SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Text Block] Long tail coverage reserves as percentage of reserves Long Tail Coverage Reserves As Percentage Of Reserves Long tail coverage reserves as a percentage of total reserves. Due after 1 year through 5 years Due after 1 year through 5 years, Percent of Total Fair Value Percentage of fair value of available for sale debt securities maturing in the second rolling twelve months through the fifth rolling twelve months following the latest balance sheet presented. Less: accumulated depreciation Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Forfeited, Weighted Average Grant Date Fair Value per Unit (in usd per share) Share based Compensation Arrangement By Share based Payment Award Equity Instruments Other Than Options Forfeited Vested In Period Weighted Average Grant Date Fair value Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeited Vested In Period Weighted Average Grant Date Fair Value Changes in plan assets and benefit obligations included in other comprehensive income (loss): Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, before Tax [Abstract] Net actuarial loss Defined Benefit Plan, Accumulated Other Comprehensive Income (Loss), Gain (Loss), before Tax Paydowns, maturities and distributions Paydowns, maturities and distributions Fair value measurement with unobservable inputs reconciliation recurring basis asset paydowns and maturities. Net unrealized investment gains (losses) included in OCI Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss) Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type [Table] Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type [Table] Schedule of future minimum lease payments under non-cancellable operating leases Lessee, Operating Lease, Liability, Maturity [Table Text Block] Basis of Presentation Basis of Accounting, Policy [Policy Text Block] Other, net Effective Income Tax Rate Reconciliation, Other Adjustments, Amount Basic (in shares) Weighted average number of common shares during the period (in shares) Shares of common stock - weighted average basic (in shares) Weighted Average Number of Shares Outstanding, Basic Basis spread on variable rate Debt Instrument, Basis Spread on Variable Rate Bank of America, N.A. Bank of America [Member] Risk-free interest rate Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate Limited partnership interests Investment in subsidiaries Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures Weighted Average Option Price per Share, Options Forfeited (in usd per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Forfeitures in Period, Weighted Average Exercise Price Gross Amount Direct Premiums Earned Carrying Value Reported Value Measurement [Member] HMLIC and NTA Horace Mann Life Insurance Company And NTA [Member] Horace Mann Life Insurance Company And NTA Plan Name [Domain] Plan Name [Domain] Entity Well-known Seasoned Issuer Entity Well-known Seasoned Issuer Stock options (in shares) Incremental Common Shares Attributable to Stock Options Incremental common shares attributable to stock options. Weighted average fair value of nonvested options outstanding (in usd per share) Weighted Average Fair Value Of Nonvested Options Outstanding Weighted average fair value of nonvested options outstanding. Actuarial loss Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, before Tax Reinsurance companies Property Liability and Casualty Insurance Reinsurance Companies [Member] Actuarial loss (gain) Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss) Shareholders' Equity and Share-Based Compensation Shareholders' Equity and Share-based Payments [Text Block] Long-term debt Long-term Debt, Fair Value Statements of Cash Flows Cash and Cash Equivalents, Policy [Policy Text Block] Transfers out of Level 3 Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3 Income tax expense Total income tax expense Income tax benefit Income Tax Expense (Benefit) Investment Income [Table] Investment Income [Table] Cash Cash at beginning of year Cash at end of year Total cash and restricted cash shown in the Consolidated Statements of Cash Flows Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents Property and Equipment Property, Plant and Equipment, Policy [Policy Text Block] Debt Securities, Available-for-sale [Table] Debt Securities, Available-for-sale [Table] Purchases Purchase of equity securities Payments to Acquire Marketable Securities Indefinite-lived Intangible Assets, Major Class Name [Domain] Indefinite-lived Intangible Assets, Major Class Name [Domain] Local Phone Number Local Phone Number Derivative Instruments and Hedging Activities Disclosure [Abstract] Derivative Instruments and Hedging Activities Disclosure [Abstract] Percent of Total Fair Value Percentage of Total Fair Value [Abstract] Percentage of Total Fair Value [Abstract] Deferred policy acquisition costs, impact of unrealized investment gains (losses) Deferred Policy Acquisition Cost Ending Impact Of Unrealized Investment Gains Losses Deferred policy acquisition cost ending impact of unrealized investment gains losses. Cumulative Effect, Period of Adoption [Domain] Cumulative Effect, Period of Adoption [Domain] option adjusted spread Measurement Input Option Adjusted Spread [Member] Measurement Input Option Adjusted Spread Distributed, Vested, Units (in shares) Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested Distributed In Period Share based compensation arrangement by share based payment award equity instruments other than options vested distributed in period. Summary of contributions to qualified defined contribution plan, 401(k), non-qualified defined contribution plan and total assets of the plans Contribution and Plan Asset Summary [Table Text Block] Tabular disclosure of contributions to employees' accounts under the qualified defined contribution plan, the 401(k) plan and the non-qualified defined contribution plan, as well as total assets of the plans. Derivative [Line Items] Derivative [Line Items] Summary of indefinite-lived intangible assets Schedule of Indefinite-Lived Intangible Assets [Table Text Block] Maximum exercise price (in usd per share) Share-based Payment Arrangement, Option, Exercise Price Range, Upper Range Limit Life insurance in force SEC Schedule, 12-17, Insurance Companies, Reinsurance, Life Insurance in Force, Net [Abstract] Indefinite-lived Intangible Assets [Roll Forward] Indefinite-lived Intangible Assets [Roll Forward] Decreases related to prior year tax positions Unrecognized Tax Benefits, Decrease Resulting from Prior Period Tax Positions Premiums written and contract deposits, Assumed from Other Companies Assumed Insurance Premiums Written And Contract Deposits Insurance premiums written and contract deposits for all insurance contracts assumed from other insurers as a result of reinsurance arrangements. SEC Schedule, 12-17, Insurance Companies, Reinsurance [Abstract] SEC Schedule, 12-17, Insurance Companies, Reinsurance [Abstract] Federal Home Loan Bank Branch [Domain] Federal Home Loan Bank Branch [Domain] Schedule of Finite-Lived Intangible Assets [Table] Schedule of Finite-Lived Intangible Assets [Table] Withdrawals and surrenders Withdrawal from Contract Holders Funds Beginning balance, Vested, Weighted Average Grant Date Fair Value per Unit (in usd per share) Ending balance, Vested, Weighted Average Grant Date Fair Value per Unit (in usd per share) Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested Weighted Average Grant Date Fair Value Share based compensation arrangement by share based payment award equity instruments other than options vested weighted average grant date fair value. Premiums written and contract deposits, Net Amount Insurance premiums written and contract deposits Insurance Premiums Written And Contract Deposits The sum of insurance premiums written for all insurance contracts after subtracting any amounts ceded to another insurer and adding premiums assumed from other insurers, plus contract deposits on investment and universal life-type contracts. Borrowing capacity Line of Credit Facility, Maximum Borrowing Capacity Weighted average assumptions used to determine expense: Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract] Award Type [Axis] Award Type [Axis] Outstanding Units, Weighted Average Grant Date Fair Value per Unit Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract] Discount rate Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate P D I interest margin Measurement Input P D I Interest Margin [Member] Measurement Input P D I Interest Margin Policy reserves Liability for Future Policy Benefits, Life Reinsurance Deposit Receivable Reinsurance Deposit Receivable [Member] Reinsurance Deposit Receivable [Member] Summarized financial information for these segments Segment Reporting Information, Profit (Loss) [Abstract] Restricted cash Restricted Cash Retained earnings Retained earnings Retained Earnings [Member] Measurement Basis [Axis] Measurement Basis [Axis] Other comprehensive income - net funded status of benefit plans Deferred Tax Assets Tax Deferred Expense Compensation and Benefits Pensions and Post Retirement Benefits Deferred tax assets tax deferred expense compensation and benefits pensions and post retirement benefits. Defined benefit plan and the supplemental defined benefit plans Schedule of Net Benefit Costs [Table Text Block] Net cash (used in) provided by investing activities Net Cash Provided by (Used in) Investing Activities Total Outstanding Options, Weighted Average Remaining Term Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term Award Type [Domain] Award Type [Domain] Life and Annuity segments Life and Annuity Segments Combined [Member] Long-term debt Long-term Debt, Unclassified [Abstract] Corporate bonds Corporate bonds Corporate Debt Securities [Member] Gain (Loss) on Securities [Line Items] Gain (Loss) on Securities [Line Items] Intrinsic value Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Grant Date Intrinsic Value Reinsured amount of each loss above retention in clash event Reinsured Amount Of Each Loss Above Retention In Clash Event Reinsured amount of each loss above retention in clash event. Service cost: Cost of Goods and Services Sold [Abstract] Principal borrowings on Bank Credit Facility Proceeds from FHLBank Advance, Investing Activities Treasury stock, at cost, 2020, 24,902,579 shares; 2019, 24,850,484 shares Treasury stock, at cost, 2020, 24,902,579 shares; 2019, 24,850,484 shares Treasury Stock, Value Other policy claims and benefits payable SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Other Policy Claim and Benefit Payable Defined Benefit Plan Pension Plan Pension Plan [Member] Discount rate Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate Cash flows from financing activities Net Cash Provided by (Used in) Financing Activities, Continuing Operations [Abstract] Investment contract and policy reserves, fixed annuity contracts Investment Contract And Policy Reserves, Fixed Annuity Contracts, Fair Value Investment Contract And Policy Reserves, Fixed Annuity Contracts, Fair Value Expenses paid Defined Benefit Plan, Plan Assets, Administration Expense Paid by Employer Defined Benefit Plan, Plan Assets, Administration Expense Paid by Employer Coverage above retention per occurrence under layer two catastrophe reinsurance Coverage Above Retention Per Occurrence Under Layer Two Catastrophe Reinsurance Coverage provided above retention per occurrence under layer two of catastrophe excess of loss reinsurance coverage. Net Amount Premiums Earned, Net Adoption of New Accounting Standards and Future Adoption of New Accounting Standards New Accounting Pronouncements, Policy [Policy Text Block] Principal borrowings on Bank Credit Facility Proceeds from Lines of Credit Change in fair value of derivatives: Derivative, Gain (Loss) on Derivative, Net [Abstract] Statement of Financial Position [Abstract] Statement of Financial Position [Abstract] Year Two Short-duration Insurance Contracts, Historical Claims Duration, Year Two Basic: Basic Earnings Per Share, Basic [Abstract]