Trading Arrangements, by Individual Trading Arrangements, by Individual [Table] Trading Arrangement: Trading Arrangement [Axis] Maximum Maximum Maximum [Member] Portion at Fair Value Measurement Portion at Fair Value Measurement [Member] Title of 12(b) Security Title of 12(b) Security Subsequent Event [Member] Subsequent Event [Member] Schedule of Available-for-sale Securities [Table] Debt Securities, Available-for-Sale [Table] Carrying Amount Reported Value Measurement [Member] Derivative Assets (Liabilities), at Fair Value, Net Derivative Assets (Liabilities), at Fair Value, Net Adjustment to Compensation, Amount Adjustment to Compensation Amount Pledged Status [Axis] Pledged Status [Axis] Policyholder Account Balance Policyholder Account Balance [Table Text Block] Financial Instrument [Axis] Financial Instrument [Axis] Segment Reporting [Abstract] Segment Reporting [Abstract] Collateral Securities Repledged, Delivered, or Used Collateral Securities Repledged, Delivered, or Used Disposal Group, Including Discontinued Operation, Other Assets Disposal Group, Including Discontinued Operation, Other Assets Financial Collateral (Received) Derivative Liability, Fair Value of Collateral Derivative Instrument [Axis] Derivative Instrument [Axis] Liability for Future Policy Benefit, Weighted-Average Interest Accretion Rate Liability for Future Policy Benefit, Weighted-Average Interest Accretion Rate Servicing Asset at Fair Value, Amount Servicing Asset at Fair Value, Amount Measurement Frequency [Axis] Measurement Frequency [Axis] Consolidated Entities [Axis] Consolidated Entities [Axis] Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Original Weighted Average Loan to Value Ratio of Commercial Mortgage loan Original Weighted Average Loan to Value Ratio of Commercial Mortgage loan Original weighted average loan to value ratio of commercial mortgage loan. Asset-backed securities ("ABS") ABS Asset-Backed Securities [Member] Other Comprehensive Income (Loss), Net of Tax [Abstract] Other Comprehensive Income (Loss), Net of Tax [Abstract] Measurement Input, Credit Spread [Member] Measurement Input, Credit Spread [Member] Policyholder Account Balance, above Guaranteed Minimum Crediting Rate [Axis] Policyholder Account Balance, above Guaranteed Minimum Crediting Rate [Axis] Consolidated Entities [Domain] Consolidated Entities [Domain] Regional Shopping Malls Regional Shopping Malls [Member] Regional Shopping Malls Originated Three Years Before Latest Fiscal Year Originated Three Years before Latest Fiscal Year [Member] Originated Three Years before Latest Fiscal Year [Domain] Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total Debt Securities, Available-for-Sale, Unrealized Loss Position, Accumulated Loss Avg. Debt-Service Coverage Ratio Average Debt Service Coverage Ratio Average debt service coverage ratio. Common Stock, Par or Stated Value Per Share Common Stock, Par or Stated Value Per Share Reclassification out of Accumulated Other Comprehensive Income [Member] Reclassification out of Accumulated Other Comprehensive Income Reclassification out of Accumulated Other Comprehensive Income [Member] Catastrophic Event [Domain] Catastrophic Event [Domain] Retirement Benefits [Abstract] Retirement Benefits [Abstract] Outstanding Aggregate Erroneous Compensation Amount Outstanding Aggregate Erroneous Compensation Amount Premiums Receivable, Gross Premiums Receivable, Gross Number of Reportable Segments Number of Reportable Segments Originated Four Years Before Latest Fiscal Year Originated Four Years before Latest Fiscal Year [Member] Originated Four Years before Latest Fiscal Year [Domain] Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months Cash Flow Hedge Gain (Loss) to be Reclassified within 12 Months Entity Address, City or Town Entity Address, City or Town Fair Value Fair Value Derivative, Fair Value, Net AOCI, Liability for Future Policy Benefit, Expected Future Policy Benefit, before Tax AOCI, Liability for Future Policy Benefit, Expected Future Policy Benefit, before Tax Receivables [Abstract] Receivables [Abstract] Statement of Financial Position [Abstract] Statement of Financial Position [Abstract] Peer Group Total Shareholder Return Amount Peer Group Total Shareholder Return Amount Provision for unpaid losses and loss adjustment expense Liability for Unpaid Claims and Claims Adjustment Expense, Incurred Claims [Abstract] Mortgage Servicing [Line Items] Mortgage Servicing [Line Items] Mortgage Servicing Significant
Observable
Inputs
(Level 2) Fair Value, Inputs, Level 2 [Member] Total Shareholder Return Vs Peer Group Total Shareholder Return Vs Peer Group [Text Block] Total other comprehensive income (loss) Other Comprehensive Income (Loss), Net of Tax Non-Rule 10b5-1 Arrangement Terminated Non-Rule 10b5-1 Arrangement Terminated [Flag] Segment Reporting, Reconciliation of Asset by Segment to Consolidated Segment Reporting, Reconciliation of Asset by Segment to Consolidated [Table Text Block] UNITED STATES UNITED STATES Insurance Loss Reserves [Abstract] Insurance Loss Reserves [Abstract] Subsequent Event Type [Axis] Subsequent Event Type [Axis] Concentration Risk Type [Axis] Concentration Risk Type [Axis] Insurance Operating Costs and Other Expenses [Member] Insurance Operating Costs and Other Expenses [Member] Insurance Operating Costs and Other Expenses Liability for Future Policy Benefit, Expected Future Policy Benefit, Benefit Payment Liability for Future Policy Benefit, Expected Future Policy Benefit, Benefit Payment Fee income Insurance Commissions and Fees Insurance Commissions and Fees OCI before reclassifications OCI, before Reclassifications, before Tax, Attributable to Parent Class of Treasury Stock [Table] Class of Treasury Stock [Table] Variable Interest Entity, Measure of Activity [Abstract] Premium Receivable, Credit Loss Expense (Reversal) Premium Receivable, Credit Loss Expense (Reversal) Reconciliation of Net Income from Segments to Consolidated Segment Reporting [Table Text Block] Municipal Municipal Bonds [Member] Use of Estimates Use of Estimates, Policy [Policy Text Block] Reinsurance Recoverables, Gross Reinsurance Recoverables, Gross Installment billing fees [Member] Installment billing fees [Member] Installment billing fees [Member] OCI, net of tax Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent Credit Derivatives [Line Items] Credit Derivatives [Line Items] Reinsurance Recoverable, Past Due [Line Items] Reinsurance Recoverable, Past Due [Line Items] AM Best, A++ Rating [Member] AM Best, A++ Rating [Member] External Credit Rating by Grouping [Domain] External Credit Rating by Grouping [Domain] Discontinued Operation, Gain (Loss) on Disposal of Discontinued Operation, Net of Tax Discontinued Operation, Gain (Loss) on Disposal of Discontinued Operation, Net of Tax Over one year through five years Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year One Through Five Document Period End Date Document Period End Date Preferred Stock, Shares Outstanding, Ending Balance Preferred Stock, Shares Outstanding Bond Surety Product Line [Member] Surety Product Line [Member] Earnings Per Share, Basic [Abstract] Earnings Per Share, Basic [Abstract] Investments, All Other Investments [Abstract] Investments, All Other Investments [Abstract] Gross losses on sales of fixed maturities Debt Securities, Available-for-Sale, Realized Loss Segment Reporting, Reconciliation of Other Item by Segment to Consolidated Segment Reporting, Reconciliation of Other Item by Segment to Consolidated [Table Text Block] Segment Reporting, Reconciliation of Revenue by Segment to Consolidated Segment Reporting, Reconciliation of Revenue by Segment to Consolidated [Table Text Block] Reclassification out of Accumulated Other Comprehensive Income [Domain] Reclassification out of Accumulated Other Comprehensive Income [Domain] Over ten years Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, after Year 10 Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent Accumulated other comprehensive income (loss) ("AOCI"), net of tax Accumulated Other Comprehensive Income (Loss), Net of Tax Entity Shell Company Entity Shell Company Consolidation Items [Domain] Consolidation Items [Domain] AOCI, Liability for Future Policy Benefit, Parent AOCI, Liability for Future Policy Benefit, Parent [Member] Mortgages [Member] Mortgages [Member] Earnings Per Common Share Earnings Per Share [Text Block] EPS Earnings Per Share [Abstract] Earnings Per Share [Abstract] Document Fiscal Period Focus Document Fiscal Period Focus Peer Group Issuers, Footnote Peer Group Issuers, Footnote [Text Block] Total liabilities Liabilities Trading Symbol Trading Symbol AARP Members [Member] AARP Members [Member] AARP Members [Member] Net disposals (additions) of property and equipment Payments to Acquire Property, Plant, and Equipment Financing Receivable, Allowance for Credit Loss [Line Items] Premium Receivable, Allowance for Credit Loss [Line Items] Financing Receivable, Allowance for Credit Loss [Line Items] Company Selected Measure Name Company Selected Measure Name Less than 65% LTV Less than 65 Percent [Member] Loan balance to adjusted collateral value less than 65%. Total realized/unrealized gains (losses), Included in OCI Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss) Transaction [Domain] Transaction [Domain] Fixed maturities, AFS Payments to Acquire Debt Securities, Available-for-Sale Income Tax Disclosure [Abstract] Income Tax Disclosure [Abstract] Contingent Consideration Payment Termination Threshold Amount - 7 Years After Closing Contingent Consideration Payment Termination Threshold Amount - 7 Years After Closing Contingent Consideration Payment Termination Threshold Amount - 7 Years After Closing Amounts reclassified from AOCI Reclassification from AOCI, Current Period, before Tax, Attributable to Parent Amortization of Deferred Gain on Retroactive Reinsurance Amortization of Deferred Gain on Retroactive Reinsurance Amortization of Deferred Gain on Retroactive Reinsurance Earnings Per Share, Diluted [Abstract] Earnings Per Share, Diluted [Abstract] Unpaid losses and loss adjustment expenses Beginning liabilities for unpaid losses and loss adjustment expenses, gross Ending liabilities for unpaid losses and loss adjustment expenses, gross Liability for Claims and Claims Adjustment Expense Operating Activities Cash Provided by (Used in) Operating Activity, Including Discontinued Operation [Abstract] Equity Valuation Assumption Difference, Footnote Equity Valuation Assumption Difference, Footnote [Text Block] Disposal Group Name [Domain] Disposal Group Name [Domain] Transfers out of Level 3 Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3 Credit Loss [Abstract] Credit Loss [Abstract] Net increases (decreases) in allowance on fixed maturities that had an allowance in a previous period Debt Securities, Available-for-Sale, Allowance for Credit Loss, Not to Sell before Recovery, Credit Loss, Previously Recorded, Expense (Reversal) U.S. Treasuries US Treasury Securities [Member] Regions [Axis] Regions [Axis] Regions [Axis] Disposal Groups, Including Discontinued Operations Disposal Groups, Including Discontinued Operations [Table Text Block] AM Best, Below B plus plus Rating [Member] AM Best, Below B plus plus Rating [Member] AM Best, Below B plus plus Rating [Member] Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block] Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block] Mortgage-backed and asset-backed securities Debt Securities, Available-for-Sale, Maturity, without Single Maturity Date, Amortized Cost Net change in other assets and other liabilities Increase (Decrease) in Other Operating Assets and Liabilities, Net Fair Value Option, Other Eligible Items Fair Value Option, Other Eligible Items [Member] Award Timing Predetermined Award Timing Predetermined [Flag] Adjustment To PEO Compensation, Footnote Adjustment To PEO Compensation, Footnote [Text Block] Stock-based compensation plans expense APIC, Share-Based Payment Arrangement, Increase for Cost Recognition Benefits, losses and loss adjustment expenses Policyholder Benefits and Claims Incurred, Net Policyholder Benefits and Claims Incurred, Net Quoted Prices in
Active Markets
for Identical
Assets
(Level 1) Fair Value, Inputs, Level 1 [Member] Liability for Unpaid Claims and Claims Adjustment Expense, Net Ending liabilities for unpaid losses and loss adjustment expenses, net Ending liabilities for unpaid losses and loss adjustment expenses, gross Liability for Unpaid Claims and Claims Adjustment Expense, Net Effective Income Tax Rate Reconciliation, Percent Effective Income Tax Rate Reconciliation, Percent Package business Package Business [Member] Package business. 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Claims Adjustment Expense, Claims Paid [Abstract] Percentage of After-Tax Available Cash Used to Determine Contingent Consideration Percentage of After-Tax Available Cash Used to Determine Contingent Consideration Percentage of After-Tax Available Cash Used to Determine Contingent Consideration One year or less Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, Year One Fair Value Disclosures [Abstract] Fair Value Disclosures [Abstract] Withdrawals and other deductions from investment and universal life-type contracts Withdrawal from Contract Holders Funds Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] Automobile Automobiles [Member] Automobiles [Member] Policyholder Dividends, Expense Policyholder Dividends, Expense Dividends paid on common stock Payments of Ordinary Dividends, Common Stock Expiration Date Trading Arrangement Expiration Date Hedging Relationship [Axis] Hedging Relationship [Axis] Reserve Line [Axis] Reserve Line [Axis] Reserve Line Accumulated Other Comprehensive Income (Loss) [Line Items] Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items] Liability for Future Policy Benefit, Expected Future Benefit, Original Discount Rate, before Reinsurance, after Cash Flow Change Liability for Future Policy Benefit, Expected Future Benefit, Original Discount Rate, before Reinsurance, after Cash Flow Change Balance Sheet Line Items [Domain] Balance Sheet Line Items [Domain] Balance Sheet Line Items Disposal Group, Including Discontinued Operations [Line Items] Disposal Group, Including Discontinued Operations [Line Items] Aggregate Pension Adjustments Service Cost Aggregate Pension Adjustments Service Cost [Member] Derivative [Table] Derivative [Table] Measurement Input, Default Rate [Member] Measurement Input, Default Rate [Member] Limited partnership and other alternative investments Proceeds from Limited Partnership Investments P&C Personal Insurance P&C Personal Insurance [Member] P&C Personal Insurance Investing Activities Cash Provided by (Used in) Investing Activity, Including Discontinued Operation [Abstract] Workers' Compensation Workers' Compensation [Member] Workers' Compensation Amortized Cost [Member] Amortized Cost [Member] Amortized Cost [Member] Disposal Groups, Including Discontinued Operations [Table] Disposal Groups, Including Discontinued Operations [Table] Segments [Domain] Segments [Domain] Interest rate swaps Interest Rate Swap [Member] Standard & Poor's, BB- Rating Standard & Poor's, BB- Rating [Member] Return of shares under incentive and stock compensation plans to treasury stock Shares Issued, Shares, Share-Based Payment Arrangement, Forfeited Disposal Group Classification [Domain] Disposal Group Classification [Domain] Mortgage loans (net of ACL of $49 and $49) Financing Receivable, after Allowance for Credit Loss Financing Receivable, after Allowance for Credit Loss Financing Receivable, after Allowance for Credit Loss Fixed maturities, at fair value using the fair value option ("FVO Securities") Fair Value, Option, Fixed Maturity Securities Fair Value, Option, Fixed Maturity Securities Value Type [Domain] Value Type [Domain] [Domain] for Value Type [Axis] Credit Quality Information [Abstract] Credit Quality Information [Abstract] PEO Actually Paid Compensation Amount PEO Actually Paid Compensation Amount Mortgage loans Proceeds from Sale and Collection of Mortgage Notes Receivable Fair Value Debt Securities, Available-for-Sale, Fair Value, Fiscal Year Maturity [Abstract] Policyholder Account Balance, above Guaranteed Minimum Crediting Rate [Domain] Policyholder Account Balance, above Guaranteed Minimum Crediting Rate [Domain] Liability for Claims and Claims Adjustment Expense [Line Items] Liability for Claims and Claims Adjustment Expense [Line Items] ACL Premium Receivable, Allowance for Credit Loss Premium Receivable, Allowance for Credit Loss Dividends declared on common stock Dividends, Common Stock, Cash Total stockholders’ equity Beginning balance Ending balance Equity, Attributable to Parent Region Others [Member] Region Others [Member] Region others. Real Estate [Domain] Real Estate [Domain] Assets Assets [Abstract] Variable Interest Entity, Primary Beneficiary, Maximum Loss Exposure, Amount Variable Interest Entity, Primary Beneficiary, Maximum Loss Exposure, Amount Other investments Other Investments Debt Securities, Available-for-sale, Amortized Cost Fixed maturities, available-for-sale, at fair value, amortized cost Debt Securities, Available-for-Sale, Amortized Cost Loans Credit Quality Financing Receivable Credit Quality Indicators [Table Text Block] Insider Trading Policies and Procedures [Line Items] Policyholder Account Balance, Surrender and Withdrawal Policyholder Account Balance, Surrender and Withdrawal Liabilities Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] Total provision for unpaid losses and loss adjustment expenses Total provision for unpaid losses and loss adjustment expenses Liability for Unpaid Claims and Claims Adjustment Expense, Incurred Claims Entity Central Index Key Entity Central Index Key Policyholder Account Balance, Weighted Average Crediting Rate Policyholder Account Balance, Weighted Average Crediting Rate Over the Counter [Member] Over-the-Counter [Member] Equity [Abstract] Equity [Abstract] Dividends or Other Earnings Paid on Equity Awards not Otherwise Reflected in Total Compensation for Covered Year Dividends or Other Earnings Paid on Equity Awards not Otherwise Reflected in Total Compensation for Covered Year [Member] ProceedsPaymentsIssuanceReturnOfSharesUnderIncentiveAndShareBasedCompensationPlans ProceedsPaymentsIssuanceReturnOfSharesUnderIncentiveAndShareBasedCompensationPlans ProceedsPaymentsIssuanceReturnOfSharesUnderIncentiveAndShareBasedCompensationPlans Liabilities held for sale Disposal Group, Including Discontinued Operation, Liabilities Universal Life Universal Life [Member] Schedule of Investments [Line Items] Schedule of Investments [Line Items] Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] Liability for Claims and Claims Adjustment Expense [Table] Liability for Claims and Claims Adjustment Expense [Table] Dividends declared on preferred stock Dividends, Preferred Stock, Cash Designated as Hedging Instrument Designated as Hedging Instrument [Member] Total Fixed Maturities, AFS Total Fixed Maturities, AFS Fixed Maturities [Member] Investments Investment Holdings [Text Block] AOCI Attributable to Parent [Member] AOCI Attributable to Parent [Member] All Individuals All Individuals [Member] Debt Securities, Available-for-sale, Restricted Debt Securities, Available-for-Sale, Restricted Assets Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] Net Realized Capital Gains (Losses) Realized Gain (Loss) on Investments [Table Text Block] Commitments and Contingencies, Policy [Policy Text Block] Commitments and Contingencies, Policy [Policy Text Block] Cover page. Condensed Balance Sheet Statements, Captions [Line Items] Statement [Line Items] Total assets Total assets Assets Schedule of Defined Benefit Plans Disclosures [Table] Defined Benefit Plan [Table] Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Asset, Gain (Loss), Statement of Other Comprehensive Income or Comprehensive Income [Extensible Enumeration] Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Asset, Gain (Loss), Statement of Other Comprehensive Income or Comprehensive Income [Extensible Enumeration] Premium Receivable, Allowance for Credit Loss, Writeoff Premium Receivable, Allowance for Credit Loss, Writeoff Credit derivatives in offsetting positions Credit Derivatives in Offsetting Positions [Member] The Company has entered into offsetting credit default swaps to terminate certain existing credit default swaps, thereby offsetting the future changes in value of, or losses paid related to, the original swap. Equity Securities, FV-NI, Realized Gain (Loss) Equity Securities, FV-NI, Realized Gain (Loss) Paid Up Life Paid Up Life [Member] Paid Up Life Variable Interest Entity, Not Primary Beneficiary [Member] Variable Interest Entity, Not Primary Beneficiary [Member] Liability for Future Policy Benefit Activity [Table] Liability for Future Policy Benefit Activity [Table] Operating Segments [Member] Operating Segments [Member] Disposal Group, Including Discontinued Operations, Expenses Disposal Group, Including Discontinued Operations, Expenses Disposal Group, Including Discontinued Operations, Expenses Disposal Group, Including Discontinued Operation, Revenue Disposal Group, Including Discontinued Operation, Revenue Expected Pre-Closing Dividend from Discontinued Operation Expected Pre-Closing Dividend from Discontinued Operation Expected Pre-Closing Dividend from Discontinued Operation Gross Unrealized Gains, fixed maturities, available-for-sale Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Gain, before Tax Mortgage-backed and asset-backed securities Debt Securities, Available-for-Sale, Maturity, without Single Maturity Date, Fair Value PEO PEO [Member] Goodwill Goodwill Retirement Plan Type [Axis] Retirement Plan Type [Axis] Forgone Recovery due to Violation of Home Country Law, Amount Forgone Recovery due to Violation of Home Country Law, Amount Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions Liabilities for Guarantees on Long-Duration Contracts [Line Items] Liability for Future Policy Benefit, Activity [Line Items] Credit Rating, AM Best [Axis] Credit Rating, AM Best [Axis] Depositary Shares, Each Representing a 1/1,000th Interest in a Share of 6.000% Non-Cumulative Preferred Stock, Series G, par value $0.01 per share Noncumulative Preferred Stock [Member] Equity securities Equity Securities, FV-NI, Gain (Loss) Discontinued Operations, Disposed of by Sale Discontinued Operations, Disposed of by Sale [Member] Retained Earnings Retained Earnings [Member] Insurance operating costs and other expenses Operating Expenses Discontinued Operations, Disposed of by Sale [Axis] Discontinued Operations, Disposed of by Sale [Axis] Discontinued Operations, Disposed of by Sale Fair Value Measurement, Policy Fair Value Measurement, Policy [Policy Text Block] Amortization of actuarial loss Accumulated Defined Benefit Plans Adjustment, Net Gain (Loss) Attributable to Parent [Member] Common Shares Outstanding, beginning of period Common Shares Outstanding, at end of period Common Stock, Shares, Outstanding Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Award Timing Disclosures [Line Items] Accumulated Foreign Currency Adjustment Attributable to Parent [Member] Accumulated Foreign Currency Adjustment Attributable to Parent [Member] Professional liability Professional Liability [Member] Professional liability. Financing Receivable, Past Due [Line Items] Financing Receivable, Past Due [Line Items] Corporate Corporate Corporate Debt Securities [Member] Diluted Net income available to common stockholders Earnings Per Share, Diluted Securities for Reverse Repurchase Agreements Securities for Reverse Repurchase Agreements Deferred Profit Liability Deferred Profit Liability [Member] Deferred Profit Liability Preferred stock, $0.01 par value — 50,000,000 shares authorized, 13,800 shares issued at June 30, 2026 and December 31, 2025, aggregate liquidation preference of $345 Preferred Stock, Value, Outstanding Amortization of other intangible assets Intangible Asset, Finite-Lived, Amortization Expense Non-insurance revenues with customers Revenue from Contract with Customer, Excluding Assessed Tax Derivatives in Cash Flow Hedging Relationships Schedule of Cash Flow Hedging Instruments, Statements of Financial Performance and Financial Position, Location [Table Text Block] Schedule of Financial Instruments Owned and Pledged as Collateral Schedule of Financial Instruments Owned and Pledged as Collateral [Table Text Block] Prior year's discount accretion Liability for Unpaid Claims and Claims Adjustment Expense Prior Years Interest Liability for Unpaid Claims and Claims Adjustment Expense Prior Years Interest Financing Receivable, Allowance for Credit Loss Beginning balance Ending balance Financing Receivable, Allowance for Credit Loss Financing Receivable, Allowance for Credit Loss Equity Awards Adjustments, Footnote Equity Awards Adjustments, Footnote [Text Block] Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Period Increase (Decrease), Including Exchange Rate Effect, Discontinued Operation Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Period Increase (Decrease), Including Exchange Rate Effect, Discontinued Operation Policyholder Account Balance, Net Amount at Risk Policyholder Account Balance, Net Amount at Risk Sales Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales Reinsurance, Loss on Uncollectible Accounts in Period, Amount Reinsurance, Loss on Uncollectible Accounts in Period, Amount Net amount, liabilities Derivative Liability, Including Not Subject to Master Netting Arrangement, after Offset and Deduction Proceeds from the sale/maturity/prepayment of: Proceeds from Sale, Maturity and Collection of Investments [Abstract] Liability for Future Policy Benefit, Expected Future Gross Premium, Undiscounted, before Reinsurance Liability for Future Policy Benefit, Expected Future Gross Premium, Undiscounted, before Reinsurance Debt-to-Value [Domain] Debt-to-Value [Domain] AM Best, A- Rating [Member] AM Best, A- Rating [Member] Multifamily Multifamily [Member] Non-qualifying foreign currency derivatives Derivative, Gain (Loss) on Derivative, Net Amount [Domain] Amount [Domain] [Domain] for Amount [Axis] Originated in Fiscal Year Before Latest Fiscal Year Originated in Fiscal Year before Latest Fiscal Year [Member] Originated in Fiscal Year before Latest Fiscal Year [Domain] Group Insurance Policy [Member] Group Insurance Policy [Member] Group Insurance Policy [Member] Standard & Poor's, B- Rating Standard & Poor's, B- Rating [Member] Non-Catastrophe [Member] Non-Catastrophe [Member] Non-Catastrophe Percentage of Gross Unrealized Losses Depressed Less than Twenty Percent of Cost or Amortized Cost Percentage of Gross Unrealized Losses Depressed Less than Twenty Percent of Cost or Amortized Cost Percentage of gross unrealized losses depressed less than twenty percent of cost or amortized cost. Foreign government/government agencies Foreign Govt./Govt. Agencies Debt Security, Government, Non-US [Member] Equity Option [Member] Equity Option [Member] Rule 10b5-1 Arrangement Adopted Rule 10b5-1 Arrangement Adopted [Flag] Service cost Defined Benefit Plan, Service Cost Originated in Current Fiscal Year Originated in Current Fiscal Year [Member] Originated in Current Fiscal Year [Domain] Equity Securities [Member] Equity securities, at fair value Equity Securities [Member] Restriction [Domain] Restriction [Domain] [Domain] for Restriction [Axis] Financing Receivable, Allowance for Credit Loss [Table Text Block] Financing Receivable, Allowance for Credit Loss [Table Text Block] Common Stock, Shares, Issued Common Stock, Shares, Issued Beginning balance Ending balance Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value Policyholder Account Balance, at Guaranteed Minimum Crediting Rate Policyholder Account Balance, at Guaranteed Minimum Crediting Rate [Member] Income Statement Location [Domain] Income Statement Line Item [Domain] Income Statement Location [Domain] Measurement Input, Constant Prepayment Rate [Member] Measurement Input, Constant Prepayment Rate [Member] Debt Securities, Available-for-Sale, Allowance for Credit Loss Debt Securities, Available-for-sale, Allowance for Credit Loss, Beginning Balance Allowance for credit losses, fixed maturity, AFS Debt Securities, Available-for-Sale, Allowance for Credit Loss Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss Changes in and Reclassifications from Accumulated Other Comprehensive Income (Loss) Comprehensive Income (Loss) Note [Text Block] Product and Service [Domain] Product and Service [Domain] Catastrophe Catastrophe [Member] Compensation Actually Paid vs. Other Measure Compensation Actually Paid vs. Other Measure [Text Block] Termination Date Trading Arrangement Termination Date Discontinued Operations, Policy Discontinued Operations, Policy [Policy Text Block] Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent Fair Value, Recurring and Nonrecurring [Table] Fair Value, Recurring and Nonrecurring [Table] Disposal Groups, Including Discontinued Operations, Disclosure Disposal Groups, Including Discontinued Operations, Disclosure [Text Block] Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent Compensation Actually Paid vs. Total Shareholder Return Compensation Actually Paid vs. Total Shareholder Return [Text Block] Net Amount, assets Derivative Asset, Including Not Subject to Master Netting Arrangement, after Offset and Deduction Middle Atlantic [Member] Middle Atlantic [Member] Middle Atlantic. Current accident year Current incurral year Current Year Claims and Claims Adjustment Expense Fair Value as of Grant Date Award Grant Date Fair Value Collateral Pledged Collateral Pledged [Member] AM Best, B++ Rating [Member] AM Best, B++ Rating [Member] Other Insurance, Other [Member] Insurance, Other [Member] Pay vs Performance Disclosure, Table Pay vs Performance [Table Text Block] Remaining authorized repurchase amount Share Repurchase Program, Remaining Authorized, Amount Arrangement Duration Trading Arrangement Duration Retail Retail Site [Member] Consolidation Items [Axis] Consolidation Items [Axis] Entity Address, Postal Zip Code Entity Address, Postal Zip Code Entity Registrant Name Entity Registrant Name Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss Reinsurance recoverables (net of allowance for uncollectible reinsurance of $70 and $69) Reinsurance Recoverable, Allowance for Credit Loss Reinsurance Recoverable, Allowance for Credit Loss, Beginning Balance Reinsurance Recoverable, Allowance for Credit Loss Insider Trading Policies and Procedures Not Adopted Insider Trading Policies and Procedures Not Adopted [Text Block] Total revenues Total revenues Revenues Number of Past Due Commercial Mortgage Loans Number of Past Due Commercial Mortgage Loans Number of Past Due Commercial Mortgage Loans Limited partnerships and other alternative investments Alternative Investment Forgone Recovery due to Expense of Enforcement, Amount Forgone Recovery due to Expense of Enforcement, Amount Credit Rating, AM Best [Domain] Credit Rating, AM Best [Domain] Non-Qualifying Strategies Recognized within Net Realized Capital Gains (Losses) Non-Qualifying Strategies Recognized within Net Realized Capital Gains (Losses) [Table Text Block] Non-Qualifying Strategies Recognized within Net Realized Capital Gains (Losses) [Table Text Block] Subtotal Debt Securities, Available-for-Sale, Maturity, Allocated and Single Maturity Date, Fair Value Credit losses on fixed maturities where credit losses were not previously recorded Debt Securities, Available-for-Sale, Allowance for Credit Loss, Not Previously Recorded Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block] Award Type [Domain] Award Type [Domain] Derivative, Net Liability Position, Aggregate Fair Value Derivative, Net Liability Position, Aggregate Fair Value Fair Value Option, Disclosures [Table] Fair Value Option, Disclosures [Table] Fair Value Measurements Fair Value Disclosures [Text Block] Fair Value, Inputs, Level 3 [Member] Significant
Unobservable
Inputs
(Level 3) Fair Value, Inputs, Level 3 [Member] Asset Pledged as Collateral [Member] Asset Pledged as Collateral [Member] Liability for Future Policy Benefit, Activity [Table Text Block] Liability for Future Policy Benefit, Activity [Table Text Block] Deferred policy acquisition costs Deferred Policy Acquisition Costs and Present Value of Future Insurance Profits, Net Transaction Type [Axis] Transaction Type [Axis] Treasury stock acquired Number of shares acquired Treasury Stock, Shares, Acquired Standard & Poor's, Below BB Rating Standard & Poor's, Below BB Rating [Member] Standard & Poor's, Below BB Rating Restricted cash Restricted Cash Debt Securities, Available-for-sale, Allowance for Credit Loss [Line Items] Debt Securities, Available-for-Sale, Allowance for Credit Loss [Line Items] Fair Value Measured at Net Asset Value Per Share [Member] Fair Value Measured at Net Asset Value Per Share [Member] OCI Location [Axis] OCI Location [Axis] OCI Location Originated Five or More Years Before Latest Fiscal Year Originated Five or More Years before Latest Fiscal Year [Member] Originated Five or More Years before Latest Fiscal Year [Domain] Other assets Other Assets Other Assets Change in ACL on fixed maturities, AFS Debt Securities, Available-for-Sale, Allowance for Credit Loss, Period Increase (Decrease) Payments for (Proceeds from) Derivative Instrument, Investing Activities Payments for (Proceeds from) Derivative Instrument, Investing Activities Liability Class [Axis] Liability Class [Axis] Treasury stock acquired Value of shares acquired Treasury Stock, Value, Acquired, Cost Method Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation Amount [Axis] Amount [Axis] Amount [Axis] Derivative, Collateral, Right to Reclaim Cash Derivative Liability, Subject to Master Netting Arrangement, Collateral, Right to Reclaim Cash Not Offset Issuance of shares under incentive and stock compensation plans from treasury stock and other Stock Issued During Period, Value, Treasury Stock Reissued Reclassifications from AOCI Reclassification out of Accumulated Other Comprehensive Income [Table Text Block] Non-NEOs Non-NEOs [Member] Policyholder Account Balance, Interest Expense Policyholder Account Balance, Interest Expense Credit Derivatives by Type Disclosure of Credit Derivatives [Table Text Block] Customer [Domain] Customer [Domain] Over five years through ten years Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, after Year 5 Through 10 Equity, Class of Treasury Stock [Line Items] Equity, Class of Treasury Stock [Line Items] Noncatastrophic Event [Axis] Noncatastrophic Event [Axis] Treasury stock acquired, including related excise tax paid Payments for Repurchase of Common Stock Statistical Measurement [Axis] Statistical Measurement [Axis] Reinsurance, Excess Retention, Amount Reinsured, Per Policy Reinsurance, Excess Retention, Amount Reinsured, Per Policy Discontinued Operation, Income (Loss) from Discontinued Operation During Phase-out Period, before Income Tax Discontinued Operation, Income (Loss) from Discontinued Operation During Phase-out Period, before Income Tax Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification and Tax Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification and Tax Award Type [Axis] Award Type [Axis] Liability for Future Policy Benefit, Expected Future Policy Benefit, Cumulative Increase (Decrease) of Actual Variance from Expected Experience Liability for Future Policy Benefit, Expected Future Policy Benefit, Cumulative Increase (Decrease) of Actual Variance from Expected Experience Interest rate derivatives Interest Rate Contract [Member] Named Executive Officers, Footnote Named Executive Officers, Footnote [Text Block] Pacific [Member] Pacific [Member] Pacific. Retained earnings Retained Earnings (Accumulated Deficit) Product and Service [Axis] Product and Service [Axis] 65% - 80% LTV Between 65 to 80 Percent [Member] Loan balance to adjusted collateral value between 65% and 80%. Current Weighted Average Loan to Value Ratio of Commercial Mortgage Loan Current Weighted Average Loan to Value Ratio of Commercial Mortgage Loan Current weighted average loan to value ratio of commercial mortgage loan. Awards Close in Time to MNPI Disclosures Awards Close in Time to MNPI Disclosures [Table] Pension Plan [Member] Pension Plan [Member] Common Stock, par value $0.01 per share Common Stock Common Stock [Member] Interest rate swaps and futures Interest Rate Swaps, Swaptions and Futures [Member] Interest Rate Swaps, Swaptions and Futures [Member] Fixed maturities, AFS, at fair value (amortized cost of $47,036 and $46,871, and ACL of $16 and $16) Debt Securities, Available-for-Sale Debt Securities, Available-for-Sale, Total Debt Securities, Available-for-Sale External Credit Rating by Grouping [Axis] External Credit Rating by Grouping [Axis] Reclassification out of Accumulated Other Comprehensive Income [Table] Reclassification out of Accumulated Other Comprehensive Income [Table] South Atlantic [Member] South Atlantic [Member] South Atlantic. Reinsurance Recoverable, Allowance for Credit Loss [Abstract] Reinsurance Recoverable, Allowance for Credit Loss [Abstract] Income Statement Location [Axis] Income Statement Line Item [Axis] Income Statement Line Item Fair Value, Asset, Recurring Basis, Still Held, Unrealized Gain (Loss), OCI Fair Value, Asset, Recurring Basis, Still Held, Unrealized Gain (Loss), OCI Measurement Input, Loss Severity [Member] Measurement Input, Loss Severity [Member] Derivative Contract [Domain] Derivative Contract [Domain] Financial Asset, Past Due Financial Asset, Past Due [Member] Other Investments [Member] Derivative Financial Instruments, Assets [Member] Regions [Domain] Regions [Domain] [Domain] for Regions [Axis] Total liabilities and stockholders’ equity Liabilities and Equity Net realized gains (losses) Realized Investment Gains (Losses) Realized Investment Gains (Losses) Employee Stock Option Share-Based Payment Arrangement, Option [Member] Purchases Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases Standard & Poor's, B+ Rating Standard & Poor's, B+ Rating [Member] Property, Liability and Casualty Insurance Product Line Property, Liability and Casualty Insurance Product Line [Member] Segments [Axis] Segments [Axis] Additional 402(v) Disclosure Additional 402(v) Disclosure [Text Block] Asset Class [Axis] Asset Class [Axis] Tabular List, Table Tabular List [Table Text Block] AOCI, Gain (Loss), Debt Securities, Available-for-sale, with Allowance for Credit Loss, Parent AOCI, Gain (Loss), Debt Securities, Available-for-Sale, with Allowance for Credit Loss, Parent [Member] Standard & Poor's, AA Rating Standard & Poor's, AA Rating [Member] Additional paid-in capital Additional Paid in Capital Reinsurance and other recoverables Reinsurance Recoverable for Unpaid Claims and Claims Adjustments Reinsurance Recoverable for Unpaid Claims and Claims Adjustments Unrealized Gain (Loss) on Investments [Table Text Block] Unrealized Gain (Loss) on Investments [Table Text Block] Increase (Decrease) in Reinsurance Recoverable Increase (Decrease) in Reinsurance Recoverable Credit Derivatives Contract Type [Axis] Credit Derivatives Contract Type [Axis] Liability for Future Policy Benefit, Expected Future Policy Benefit, Issuance Liability for Future Policy Benefit, Expected Future Policy Benefit, Issuance Name Awards Close in Time to MNPI Disclosures, Individual Name Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested [Member] Debt-to-Value [Axis] Debt-to-Value [Axis] New England [Member] New England [Member] New England. Fair Value by Liability Class [Domain] Fair Value by Liability Class [Domain] Debt Instrument, Measurement Input Debt Instrument, Measurement Input Adjustment to Compensation: Adjustment to Compensation [Axis] Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0400 to 0499 Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0400 to 0499 [Member] Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0400 to 0499 Other liabilities Derivative Financial Instruments, Liabilities [Member] Rule 10b5-1 Arrangement Terminated Rule 10b5-1 Arrangement Terminated [Flag] Aggregate Erroneous Compensation Amount Aggregate Erroneous Compensation Amount Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract] Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract] Interest paid Interest Paid, Excluding Capitalized Interest, Operating Activity Translation Adjustment Functional to Reporting Currency, Increase (Decrease), Gross of Tax Translation Adjustment Functional to Reporting Currency, Increase (Decrease), Gross of Tax Hedging Designation [Axis] Hedging Designation [Axis] Debt Security Category [Axis] Debt Security Category [Axis] Total assets accounted for at fair value on a recurring basis [3] Assets, Fair Value Disclosure Assets, Fair Value Disclosure Limited partnership and other alternative investments Payments to Acquire Limited Partnership Interests Name Measure Name Pay vs Performance Disclosure [Line Items] Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV [Domain] Junior Subordinated Debentures Junior Subordinated Notes Additional Paid-in Capital Additional Paid-in Capital [Member] Goodwill, Impairment Loss Goodwill, Impairment Loss Gross Amounts Offset in the Statement of Financial Position, assets Derivative Asset, Subject to Master Netting Arrangement, Gross Liability and Collateral, Obligation to Return Cash, Offset Interest Receivable Interest Receivable Name Trading Arrangement, Individual Name Balance Sheet Line Items [Axis] Balance Sheet Line Items [Axis] Balance Sheet Line Items Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Period Increase (Decrease), Including Exchange Rate Effect, Continuing Operation Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Period Increase (Decrease), Including Exchange Rate Effect, Continuing Operation Company Selected Measure Amount Company Selected Measure Amount Premium Receivable, Allowance for Credit Loss [Table Text Block] Premium Receivable, Allowance for Credit Loss [Table Text Block] Equity Securities, FV-NI, Unrealized Gain (Loss) Equity Securities, FV-NI, Unrealized Gain (Loss) Issuance of shares under incentive and stock compensation plans and other Shares Issued, Shares, Share-Based Payment Arrangement, after Forfeiture Schedule of Accounts, Notes, Loans and Financing Receivable [Table] Accounts and Financing Receivables [Table] Equity Securities, FV-NI, Measurement Input Equity Securities, FV-NI, Measurement Input Hartford Funds Management Group, Inc Hartford Funds Management Group, Inc [Member] Hartford Funds Management Group, Inc Non-PEO NEO Non-PEO NEO [Member] Reserve Line [Domain] Reserve Line [Domain] Reserve Line [Domain] Credit derivatives Credit Risk Contract [Member] Award Timing Method Award Timing Method [Text Block] Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect, Total Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Period Increase (Decrease), Including Exchange Rate Effect and Discontinued Operation Forgone Recovery, Explanation of Impracticability Forgone Recovery, Explanation of Impracticability [Text Block] Deferred Tax Assets, Net of Valuation Allowance Deferred Tax Assets, Net of Valuation Allowance Amortization of actuarial loss Defined Benefit Plan, Amortization of Gain (Loss) Net income Net income Net Income (Loss) Attributable to Parent Erroneous Compensation Analysis Erroneous Compensation Analysis [Text Block] Investments [Member] Investments [Member] LTV Greater than 80 Percent LTV Greater than 80 Percent [Member] LTV Greater than 80 Percent Mortgage loans originated in year before latest fiscal year Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year Financing Receivable, Past Due [Table] Financing Receivable, Past Due [Table] Restatement Determination Date: Restatement Determination Date [Axis] Standard & Poor's, BBB Rating Standard & Poor's, BBB Rating [Member] Premium Receivable, Allowance for Credit Loss, Recovery Premium Receivable, Allowance for Credit Loss, Recovery Changes in AOCI, net of tax Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Standard & Poor's, BB Rating Standard & Poor's, BB Rating [Member] Restricted Investments, Current Restricted Investments, Current Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block] Disposal Group, Including Discontinued Operation, Other Liabilities Disposal Group, Including Discontinued Operation, Other Liabilities Reinsurance Disclosures [Abstract] Revenues Revenues [Abstract] Changes in fair value of assets using fair value option Fair Value, Option, Changes in Fair Value, Gain (Loss) FVO securities Proceeds From Sale and Maturity of Fair Value Option, Fixed Maturity Securties Proceeds From Sale and Maturity of Fair Value Option, Fixed Maturity Securties Disposal Group, Including Discontinued Operations, Net Investment Income Disposal Group, Including Discontinued Operations, Net Investment Income Disposal Group, Including Discontinued Operations, Net Investment Income Collateral Already Posted, Aggregate Fair Value Collateral Already Posted, Aggregate Fair Value Pension Benefits Adjustments, Footnote Pension Benefits Adjustments, Footnote [Text Block] Statistical Measurement [Domain] Statistical Measurement [Domain] Document Fiscal Year Focus Document Fiscal Year Focus Loss on Discontinuation of Cash Flow Hedge Due to Forecasted Transaction Probable of Not Occurring Loss on Discontinuation of Cash Flow Hedge Due to Forecasted Transaction Probable of Not Occurring Customer [Axis] Customer [Axis] Liability for Unpaid Claims and Claims Adjustment Expense, Activity in Liability [Abstract] Liability for Unpaid Claims and Claims Adjustment Expense, Activity in Liability [Abstract] Common Stock, Value, Issued Common Stock, Value, Issued Depreciation and amortization Depreciation, Amortization and Accretion, Net Interest expense Interest Expense Interest Expense, Operating and Nonoperating Short-Duration Insurance, Other Short-Duration Insurance, Other [Member] Restatement Determination Date Restatement Determination Date Cash collateral held Derivative Asset, Subject to Master Netting Arrangement, Collateral, Obligation to Return Cash, Offset Against Derivative Asset Expected return on plan assets Defined Benefit Plan, Expected Return (Loss) on Plan Assets Industrial Industrial Property [Member] Origination Date [Domain] Origination Date [Domain] [Domain] for Origination Date [Axis] Amendment Flag Amendment Flag Disposal Group Classification [Axis] Disposal Group Classification [Axis] Administrative services Administrative services fees [Member] Administrative services fees [Member] Net investment income Net Investment Income Net Investment Income Gross Unrealized Losses, fixed maturities, available-for-sale Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Loss, before Tax Loss Contingencies [Table] Loss Contingencies [Table] Liability for Future Policy Benefit, Expected Future Policy Benefit, Original Discount Rate, before Cash Flow and Reinsurance Liability for Future Policy Benefit, Expected Future Policy Benefit, Original Discount Rate, before Cash Flow and Reinsurance SOFR Plus Two Point One Two Five Percent Plus Zero Point Two Six One Six One Percent Junior Subordinated Notes Due Two Thousand Sixty Seven SOFR Plus Two Point One Two Five Percent Plus Zero Point Two Six One Six One Percent Junior Subordinated Notes Due Two Thousand Sixty Seven [Member] SOFR Plus Two Point One Two Five Percent Plus Zero Point Two Six One Six One Percent Junior Subordinated Notes Due Two Thousand Sixty Seven West South Central [Member] West South Central [Member] West South Central. Investments [Domain] Investments [Domain] Offsetting Fair Value Derivative, Fair Value, Amount Offset Against Collateral, Net Liability for Unpaid Claim and Claim Adjustment Expense, Change [Table] Liability for Unpaid Claim and Claim Adjustment Expense, Change [Table] Net change in accrued and deferred income taxes Increase (Decrease) in Deferred Income Taxes Adjustment to Non-PEO NEO Compensation Footnote Adjustment to Non-PEO NEO Compensation Footnote [Text Block] Transfers into Level 3 Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3 Entity Address, State or Province Entity Address, State or Province Change in foreign currency translation adjustments Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax, Portion Attributable to Parent PEO Total Compensation Amount PEO Total Compensation Amount Captives [Member] Captives [Member] Captives [Member] Assets accounted for at fair value on a recurring basis Assets, Fair Value Disclosure [Abstract] Share Repurchase Program [Domain] Share Repurchase Program [Domain] Derivative, Notional Amount Derivative, Notional Amount Weighted average common shares outstanding, basic Weighted Average Number of Shares Outstanding, Basic Reinsurance Recoverable, Past Due [Table] Reinsurance Recoverable, Past Due [Table] Earned premiums and fee income Earned premiums and fee income Earned premiums and fee income Loss Contingencies [Line Items] Loss Contingencies [Line Items] Transfer to Investments Transfer to Investments Additions to deferred policy acquisition costs Increase (Decrease) in Deferred Policy Acquisition Costs Financing Receivable, Credit Quality Indicator [Line Items] Financing Receivable, Credit Quality Indicator [Line Items] Schedule of Investments [Abstract] Debt Securities, Available-for-sale, Allowance for Credit Loss [Table Text Block] Debt Securities, Available-for-Sale, Allowance for Credit Loss [Table Text Block] Premiums Receivable Note [Text Block] Premiums Receivable Note [Text Block] Investments: Investments [Abstract] Investments [Abstract] Over five years through ten years Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year 5 Through 10 Increase (Decrease) in Deferred Revenue Increase (Decrease) in Deferred Revenue Long-Duration Insurance, Other Long-Duration Insurance, Other [Member] Amortized Cost Debt Securities, Available-for-Sale, Amortized Cost, Fiscal Year Maturity [Abstract] Amortization of deferred policy acquisition costs Deferred Policy Acquisition Costs and Present Value of Future Insurance Profits, Amortization Defined Benefit Plan Disclosure [Line Items] Defined Benefit Plan Disclosure [Line Items] Group life Life Insurance Product Line [Member] Life Insurance Product Line [Member] Assets held for sale Disposal Group, Including Discontinued Operation, Assets Award Timing MNPI Disclosure Award Timing MNPI Disclosure [Text Block] Basis of Presentation Basis of Accounting, Policy [Policy Text Block] Dividends paid on preferred stock Payments of Ordinary Dividends, Preferred Stock and Preference Stock Class of Stock [Axis] Class of Stock [Axis] West North Central [Member] West North Central [Member] West North Central. Net income available to common stockholders Net Income (Loss) Available to Common Stockholders, Basic Additional Cash Flow Elements, Operating Activities Additional Cash Flow Elements and Supplemental Cash Flow Information [Abstract] Receivable [Domain] Receivable [Domain] Increase in insurance liabilities Increase (Decrease) in Insurance Liabilities Reinsurance Recoverable, Credit Loss Expense (Reversal) Reinsurance Recoverable, Credit Loss Expense (Reversal) Payments for the purchase of: Payment for Investing Activity [Abstract] Derivative, Nominal Value, Amount Offset Against Collateral, Net Derivative, Nominal Value, Amount Offset Against Collateral, Net Derivative, Nominal Value, Amount Offset Against Collateral, Net Treasury Stock, Value Treasury Stock, Value Financing Receivable, Allowance for Credit Loss, Writeoff Financing Receivable, Allowance for Credit Loss, Writeoff Premiums receivable, excluding receivables for losses within a deductible and retrospectively-rated policy premiums ("loss sensitive business") Premiums Receivable, Due in One Year or Less, Excluding Receivables for Loss within a Deductible and Retrospectively-Rated Policy Premiums [Member] Premiums Receivable, Due in One Year or Less, Excluding Receivables for Loss within a Deductible and Retrospectively-Rated Policy Premiums [Member] Premiums Receivable, Due in One Year or Less, Excluding Receivables for Loss within a Deductible and Retrospectively-Rated Policy Premiums Long-term debt Long-Term Debt Unallocated loss adjustment expense [Axis] Unallocated loss adjustment expense [Axis] Unallocated loss adjustment expense [Axis] Net cash used for investing activities Cash Provided by (Used in) Investing Activity, Including Discontinued Operation Equity Awards Adjustments, Excluding Value Reported in Compensation Table Equity Awards Adjustments, Excluding Value Reported in the Compensation Table [Member] Residential Real Estate [Member] Residential Real Estate [Member] Derivative, Collateral, Obligation to Return Cash Derivative Asset, Subject to Master Netting Arrangement, Collateral, Obligation to Return Cash Not Offset Equity Equity [Text Block] Security Exchange Name Security Exchange Name Gross Amounts Offset in the Statement of Financial Position, liabilities Derivative Liability, Subject to Master Netting Arrangement, Gross Asset and Collateral, Right to Reclaim Cash, Offset Discontinued Operations, Disposed of by Sale [Domain] Discontinued Operations, Disposed of by Sale [Domain] Discontinued Operations, Disposed of by Sale Summary of Credit Derivatives [Abstract] Summary of Credit Derivatives [Abstract] Financing Receivable, before Allowance for Credit Loss Financing Receivable, before Allowance for Credit Loss Financing Receivable, before Allowance for Credit Loss Valuation Approach and Technique [Axis] Valuation Approach and Technique [Axis] Equity securities, at fair value Payments to Acquire Marketable Securities Total liabilities accounted for at fair value on a recurring basis Liabilities, Fair Value Disclosure Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer Mortgage loans Payments to Acquire Mortgage Notes Receivable Statement of Comprehensive Income [Abstract] Statement of Comprehensive Income [Abstract] Name Outstanding Recovery, Individual Name Equity securities, at fair value Proceeds from Sale and Maturity of Marketable Securities Award Timing, How MNPI Considered Award Timing, How MNPI Considered [Text Block] Loss Contingency, Settlement [Abstract] Loss Contingency, Settlement [Abstract] Derivative, Collateral, Right to Reclaim Securities Derivative Liability, Subject to Master Netting Arrangement, Collateral, Right to Reclaim Security Not Offset Liability for Future Policy Benefits and Unpaid Claims and Claims Adjustment Expense [Abstract] Liability for Future Policy Benefits and Unpaid Claims and Claims Adjustment Expense [Abstract] Cash Consideration Receivable Upon Sale of Business Cash Consideration Payable Upon Close of Business Sale Cash Consideration Payable Upon Close of Business Sale Property & Casualty Other Operations [Member] Property & Casualty Other Operations [Member] Property & Casualty Other Operations [Member] Prior Year End Fair Value of Equity Awards Granted in Any Prior Year that Fail to Meet Applicable Vesting Conditions During Covered Year Prior Year End Fair Value of Equity Awards Granted in Any Prior Year that Fail to Meet Applicable Vesting Conditions During Covered Year [Member] Marine Marine [Member] Marine [Member] Pension Adjustments Prior Service Cost Pension Adjustments Prior Service Cost [Member] Life Conversions Life Conversions [Member] Life Conversions Liability for Future Policy Benefit, Expected Future Policy Benefit, Undiscounted, before Reinsurance Liability for Future Policy Benefit, Expected Future Policy Benefit, Undiscounted, before Reinsurance Schedule of Investments [Table] Schedule of Investments [Table] Foreign currency swaps Foreign Currency Swaps and Forwards [Member] Foreign Currency Swaps and Forwards [Member] Change in unrealized losses on fixed maturities for which an allowance for credit losses has been recorded OCI, Debt Securities, Available-for-Sale, Gain (Loss), after Adjustment and Tax Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member] Pension and Other Postretirement Plan Adjustments Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member] Debt Securities [Member] Debt Securities [Member] Asset Class [Domain] Asset Class [Domain] Compensation Amount Outstanding Recovery Compensation Amount Individual: Individual [Axis] Weighted average common shares outstanding and dilutive potential common shares Weighted Average Number of Shares Outstanding, Diluted Receivables for Loss Sensitive Business Premiums Receivable, Loss Within a Deductible and 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Amounts of Recognized (Liabilities) Derivative Liability, Subject to Master Netting Arrangement, before Offset Variable Interest Entity, Reporting Entity Involvement, Commitments Variable Interest Entity, Reporting Entity Involvement, Commitments Variable Interest Entity, Reporting Entity Involvement, Commitments Accrued Investment Income Receivable Accrued Investment Income Receivable Interest rate swaps and futures Interest Rate Swaps and Futures [Member] Interest Rate Swaps and Futures [Member] Derivative Instrument Detail [Abstract] Derivative Instrument Detail [Abstract] Treasury Stock, Common Treasury Stock, Common [Member] Debt Securities, Available-for-sale [Line Items] Debt Securities, Available-for-Sale [Line Items] Cash Provided by (Used in) Operating Activity, Discontinued Operation Cash Provided by (Used in) Operating Activity, Discontinued Operation Mortgage loans originated two years before latest fiscal year Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year Short-duration Insurance Contracts, Liability for Unpaid Claims and Allocated Claim Adjustment Expense, Net, Not Separately Presented Short-Duration Insurance Contracts, Liability for Unpaid Claims and Allocated Claim Adjustment Expense, Net, Not Separately Presented Transfers and Servicing [Abstract] Transfers and Servicing [Abstract] Commercial Loan [Member] Commercial Loan [Member] Noncatastrophic Event [Domain] Noncatastrophic Event [Domain] Current Year Claims and Claims Adjustment Expense Type [Domain] Current Year Claims and Claims Adjustment Expense Type [Domain] Current Year Claims and Claims Adjustment Expense Type Reinsurance Recoverable, Credit Quality Indicator [Table Text Block] Reinsurance Recoverable, Credit Quality Indicator [Table Text Block] Continuing Involvement with Derecognized Transferred Financial Assets, Amount Outstanding Continuing Involvement with Derecognized Transferred Financial Assets, Amount Outstanding All Executive Categories All 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Operations, Per Basic Share Income (Loss) from Continuing Operations, Per Basic Share Average Term of Credit Risk Derivatives Less than 1 Year Average Term of Credit Risk Derivatives Less than 1 Year Average Term of Credit Risk Derivatives Less than 1 Year Investment Program, Proportional Amortization Method, Applied, Amortization Expense Investment Program, Proportional Amortization Method, Applied, Amortization Expense Non-Rule 10b5-1 Arrangement Adopted Non-Rule 10b5-1 Arrangement Adopted [Flag] Policyholder Account Balance, Premium Received Policyholder Account Balance, Premium Received Aggregate Grant Date Fair Value of Equity Award Amounts Reported in Summary Compensation Table Aggregate Grant Date Fair Value of Equity Award Amounts Reported in Summary Compensation Table [Member] Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] Other liabilities Other Liabilities Net periodic cost (benefit) Defined Benefit Plan, Net Periodic Benefit Cost (Credit) Disposal Group, Including Discontinued Operation, Operating Expense Disposal Group, Including Discontinued Operation, Operating Expense Financing Receivable, Allowance for Credit Loss [Table] Premium Receivable, Allowance for Credit Loss [Table] Financing Receivable, Allowance for Credit Loss [Table] Common Stock, Shares Authorized Common Stock, Shares Authorized Accumulated Other Comprehensive Income (Loss) [Line Items] Accumulated Other Comprehensive Income (Loss) [Line Items] Debt Securities, Available-for-sale, Realized Gain Debt Securities, Available-for-Sale, Realized Gain Over ten years Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year 10 Schedule of Carrying Values and Estimated Fair Values of Debt Instruments Schedule of Carrying Values and Estimated Fair Values of Debt Instruments [Table Text Block] Exercise Price Award Exercise Price Fair Value, Recurring [Member] Fair Value, Measurements, Recurring Fair Value, Recurring [Member] Stock repurchase authorization amount Share Repurchase Program, Authorized, Amount Segment Reporting [Line Items] Segment Reporting [Line Items] Document Quarterly Report Document Quarterly Report Year-over-Year Change in Fair Value of Equity Awards Granted in Prior Years That are Outstanding and Unvested Year-over-Year Change in Fair Value of Equity Awards Granted in Prior Years That are Outstanding and Unvested [Member] 8/1/2026 - 12/31/2029 8/1/2026 - 12/31/2028 [Member] 8/1/2026 - 12/31/2028 Realized Investment Gains Losses Realized Investment Gains Losses [Member] Realized Investment Gains Losses Employee Benefit Plans Compensation and Employee Benefit Plans [Text Block] Effect of Exchange Rate on Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Including Disposal Group and Discontinued Operations Effect of Exchange Rate on Cash, Cash 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