| Finance Lease, Right-of-Use Asset, before Accumulated Amortization | 1.62B | as of 2025-12-31 |
| Finance Lease, Right-of-Use Asset, Accumulated Amortization | 528.00M | as of 2025-12-31 |
| Accounts Payable, Trade, Current | 17.64B | as of 2025-12-31 |
| Current Federal Tax Expense (Benefit) | -217.00M | 2025-01-01 → 2025-12-31 |
| Current State and Local Tax Expense (Benefit) | 409.00M | 2025-01-01 → 2025-12-31 |
| Current Foreign Tax Expense (Benefit) | 114.00M | 2025-01-01 → 2025-12-31 |
| Current Income Tax Expense (Benefit) | 306.00M | 2025-01-01 → 2025-12-31 |
| Cash and Cash Equivalents, Fair Value Disclosure | 8.45B | as of 2025-12-31 |
| Deferred Federal Income Tax Expense (Benefit) | 92.00M | 2025-01-01 → 2025-12-31 |
| Deferred State and Local Income Tax Expense (Benefit) | 10.00M | 2025-01-01 → 2025-12-31 |
| Deferred Foreign Income Tax Expense (Benefit) | 0 | 2025-01-01 → 2025-12-31 |
| Operating Lease, Liability, Current | 1.74B | as of 2025-12-31 |
| Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense | 42.00M | 2025-01-01 → 2025-12-31 |
| Property, Plant, and Equipment and Finance Lease Right-of-Use Asset, before Accumulated Depreciation and Amortization | 37.83B | as of 2025-12-31 |
| Property, Plant, and Equipment and Finance Lease Right-of-Use Asset, Accumulated Depreciation and Amortization | 24.74B | as of 2025-12-31 |
| Property, Plant, and Equipment and Finance Lease Right-of-Use Asset, after Accumulated Depreciation and Amortization | 13.08B | as of 2025-12-31 |
| State and Local Income Tax Expense (Benefit), Continuing Operations | 419.00M | 2025-01-01 → 2025-12-31 |
| FederalStateAndLocalIncomeTaxExpenseBenefitContinuingOperations | -125.00M | 2025-01-01 → 2025-12-31 |
| Share-based Payment Arrangement, Expense | 535.00M | 2025-01-01 → 2025-12-31 |
| Foreign Income Tax Expense (Benefit), Continuing Operations | 114.00M | 2025-01-01 → 2025-12-31 |
| Effective Income Tax Rate Reconciliation at Federal Statutory Income Tax Rate, Amount | 449.00M | 2025-01-01 → 2025-12-31 |
| Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Amount | 340.00M | 2025-01-01 → 2025-12-31 |
| EffectiveIncomeTaxRateReconciliationGiltiAmount | 38.00M | 2025-01-01 → 2025-12-31 |
| Financial Liabilities Fair Value Disclosure | 0 | as of 2025-12-31 |
| EffectiveIncomeTaxRateReconciliationCrossBorderOtherAmount | 27.00M | 2025-01-01 → 2025-12-31 |
| EffectiveIncomeTaxRateReconciliationCrossBorderTaxEffectAmount | 65.00M | 2025-01-01 → 2025-12-31 |
| Effective Income Tax Rate Reconciliation, Tax Credit, Research, Amount | 50.00M | 2025-01-01 → 2025-12-31 |
| EffectiveIncomeTaxRateReconciliationTaxCreditEnergyRelatedAmount | 76.00M | 2025-01-01 → 2025-12-31 |
| Direct Premiums Earned | 135.49B | 2025-01-01 → 2025-12-31 |
| Effective Income Tax Rate Reconciliation, Tax Credit, Other, Amount | 16.00M | 2025-01-01 → 2025-12-31 |
| Ceded Premiums Earned | 1.31B | 2025-01-01 → 2025-12-31 |
| Effective Income Tax Rate Reconciliation, Tax Credit, Amount | 167.00M | 2025-01-01 → 2025-12-31 |
| Assumed Premiums Earned | 573.00M | 2025-01-01 → 2025-12-31 |
| Effective Income Tax Rate Reconciliation, Nondeductible Expense, Impairment Losses, Amount | 1.20B | 2025-01-01 → 2025-12-31 |
| Effective Income Tax Rate Reconciliation, Nondeductible Expense, Other, Amount | 7.00M | 2025-01-01 → 2025-12-31 |
| Effective Income Tax Rate Reconciliation, Tax Contingency, Amount | 64.00M | 2025-01-01 → 2025-12-31 |
| Dividends, Common Stock | 3.41B | 2025-01-01 → 2025-12-31 |
| Deconsolidation, Gain (Loss), Amount | 483.00M | 2025-01-01 → 2025-12-31 |
| Effective Income Tax Rate Reconciliation, Tax Exempt Income, Amount | 101.00M | 2025-01-01 → 2025-12-31 |
| Common Stocks, Including Additional Paid in Capital | 50.40B | as of 2025-12-31 |
| Effective Income Tax Rate Reconciliation, Disposition of Business, Amount | -1.79B | 2025-01-01 → 2025-12-31 |
| Debt Securities, Available-for-sale, Realized Gain | 68.00M | 2025-01-01 → 2025-12-31 |
| Debt Securities, Available-for-sale, Realized Loss | -131.00M | 2025-01-01 → 2025-12-31 |
| Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount | 0 | 2025-01-01 → 2025-12-31 |
| Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount | -7.00M | 2025-01-01 → 2025-12-31 |
| Finite-Lived Intangible Asset, Expected Amortization, Year One | 1.72B | as of 2025-12-31 |
| Finite-Lived Intangible Asset, Expected Amortization, Year Two | 1.60B | as of 2025-12-31 |
| Finite-Lived Intangible Asset, Expected Amortization, Year Three | 1.33B | as of 2025-12-31 |
| Finite-Lived Intangible Asset, Expected Amortization, Year Four | 1.25B | as of 2025-12-31 |
| Finite-Lived Intangible Asset, Expected Amortization, after Year Five | 1.22B | as of 2025-12-31 |
| Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, Year One | 815.00M | as of 2025-12-31 |
| Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, after Year One Through Five | 11.54B | as of 2025-12-31 |
| Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, after Year 5 Through 10 | 5.30B | as of 2025-12-31 |
| Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, after Year 10 | 2.99B | as of 2025-12-31 |
| Intangible Assets, Gross (Excluding Goodwill) | 44.37B | as of 2025-12-31 |
| Net Income (Loss) Available to Common Stockholders, Diluted | 1.77B | 2025-01-01 → 2025-12-31 |
| Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, Year One | 817.00M | as of 2025-12-31 |
| Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year One Through Five | 11.70B | as of 2025-12-31 |
| Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year 5 Through 10 | 5.38B | as of 2025-12-31 |
| Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year 10 | 2.85B | as of 2025-12-31 |
| HealthCareOrganizationAccountsPayableToThirdPartyPayor | 2.55B | as of 2025-12-31 |
| Reinsurance Recoverable for Unpaid Claims and Claims Adjustments | 90.00M | as of 2025-12-31 |
| Reinsurance Recoverable for Paid and Unpaid Claims and Claims Adjustments | 1.70B | as of 2025-12-31 |
| Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | 30.00M | as of 2025-12-31 |
| Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | 301.00M | as of 2025-12-31 |
| Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | 331.00M | as of 2025-12-31 |
| Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax | 449.00M | as of 2025-12-31 |
| Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax | 331.00M | as of 2025-12-31 |
| Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | 2.86B | as of 2025-12-31 |
| Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 3.48B | as of 2025-12-31 |
| Debt Securities, Available-for-sale, Unrealized Loss Position | 6.33B | as of 2025-12-31 |
| Deferred Tax Assets, Operating Loss Carryforwards | 793.00M | as of 2025-12-31 |
| Goodwill, Written off Related to Sale of Business Unit | 69.00M | 2025-01-01 → 2025-12-31 |
| Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Employee Compensation | 171.00M | as of 2025-12-31 |
| Operating Lease, Cost | 2.40B | 2025-01-01 → 2025-12-31 |
| Goodwill, Impaired, Accumulated Impairment Loss | 5.70B | as of 2025-12-31 |
| Short-term Lease, Cost | 36.00M | 2025-01-01 → 2025-12-31 |
| Variable Lease, Cost | 646.00M | 2025-01-01 → 2025-12-31 |
| Lease, Cost | 3.17B | 2025-01-01 → 2025-12-31 |
| Right-of-Use Asset Obtained in Exchange for Finance Lease Liability | 35.00M | 2025-01-01 → 2025-12-31 |
| Right-of-Use Asset Obtained in Exchange for Operating Lease Liability | 785.00M | 2025-01-01 → 2025-12-31 |
| Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Legal Settlements | 1.01B | as of 2025-12-31 |
| Finance Lease, Liability, to be Paid, Year One | 139.00M | as of 2025-12-31 |
| Finance Lease, Liability, to be Paid, Year Two | 136.00M | as of 2025-12-31 |
| Finance Lease, Liability, to be Paid, Year Three | 133.00M | as of 2025-12-31 |
| Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Deferred Rent | 4.43B | as of 2025-12-31 |
| Finance Lease, Liability, to be Paid, Year Four | 132.00M | as of 2025-12-31 |
| Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Reserves | 360.00M | as of 2025-12-31 |
| Finance Lease, Liability, to be Paid, Year Five | 129.00M | as of 2025-12-31 |
| Finance Lease, Liability, to be Paid, after Year Five | 1.29B | as of 2025-12-31 |
| Finance Lease, Liability, Payment, Due | 1.96B | as of 2025-12-31 |
| Deferred Tax Assets, Inventory | 70.00M | as of 2025-12-31 |
| Finance Lease, Liability, Undiscounted Excess Amount | 634.00M | as of 2025-12-31 |
| Lessee, Operating Lease, Liability, to be Paid, Year One | 2.63B | as of 2025-12-31 |
| Deferred Tax Assets, Deferred Income | 35.00M | as of 2025-12-31 |
| Lessee, Operating Lease, Liability, to be Paid, Year Two | 2.48B | as of 2025-12-31 |
| Lessee, Operating Lease, Liability, to be Paid, Year Three | 2.30B | as of 2025-12-31 |
| Lessee, Operating Lease, Liability, to be Paid, Year Four | 2.03B | as of 2025-12-31 |
| Lessee, Operating Lease, Liability, to be Paid, Year Five | 1.79B | as of 2025-12-31 |
| Lessee, Operating Lease, Liability, to be Paid, after Year Five | 8.17B | as of 2025-12-31 |
| Deferred Tax Assets, Investments | 0 | as of 2025-12-31 |
| Lessee, Operating Lease, Liability, to be Paid | 19.39B | as of 2025-12-31 |
| Deferred Tax Assets, Other | 456.00M | as of 2025-12-31 |
| Deferred Tax Assets, Valuation Allowance | 487.00M | as of 2025-12-31 |
| Deferred Tax Assets, Net of Valuation Allowance | 7.53B | as of 2025-12-31 |
| Lessee, Operating Lease, Liability, Undiscounted Excess Amount | 4.01B | as of 2025-12-31 |
| Deferred Tax Liabilities, Gross | 11.36B | as of 2025-12-31 |
| Deferred Policy Acquisition Cost, Capitalization | 516.00M | 2025-01-01 → 2025-12-31 |
| Long-term Debt, Gross | 63.71B | as of 2025-12-31 |
| Assets, Fair Value Disclosure | 37.50B | as of 2025-12-31 |
| Deferred Tax Liabilities, Investments | 134.00M | as of 2025-12-31 |
| Deferred Tax Liabilities, Leasing Arrangements | 3.87B | as of 2025-12-31 |
| Deferred Tax Liabilities, Net | 3.83B | as of 2025-12-31 |
| Liability for Unpaid Claims and Claims Adjustment Expense, Business Acquisitions | 0 | 2025-01-01 → 2025-12-31 |
| Long-Term Debt, Maturity, Year One | 4.01B | as of 2025-12-31 |
| Current Year Claims and Claims Adjustment Expense | 127.26B | 2025-01-01 → 2025-12-31 |
| Long-Term Debt, Maturity, Year Two | 3.38B | as of 2025-12-31 |
| Defined Contribution Plan, Employer Discretionary Contribution Amount | 657.00M | 2025-01-01 → 2025-12-31 |
| Long-Term Debt, Maturity, Year Three | 5.01B | as of 2025-12-31 |
| Prior Year Claims and Claims Adjustment Expense | -1.98B | 2025-01-01 → 2025-12-31 |
| Liability for Unpaid Claims and Claims Adjustment Expense, Incurred Claims | 125.27B | 2025-01-01 → 2025-12-31 |
| Liability for Unpaid Claims and Claims Adjustment Expense, Claims Paid, Current Year | 113.02B | 2025-01-01 → 2025-12-31 |
| Long-Term Debt, Maturity, Year Four | 3.76B | as of 2025-12-31 |
| Liability for Unpaid Claims and Claims Adjustment Expense, Claims Paid, Prior Years | 11.91B | 2025-01-01 → 2025-12-31 |
| Long-Term Debt, Maturity, Year Five | 4.26B | as of 2025-12-31 |
| Long-Term Debt, Maturity, after Year Five | 43.30B | as of 2025-12-31 |
| Debt Securities, Available-for-sale, Allowance for Credit Loss | 0 | as of 2025-12-31 |
| Debt Instrument, Unamortized Premium | 156.00M | as of 2025-12-31 |
| Interest Rate Cash Flow Hedge Gain (Loss) to be Reclassified During Next 12 Months, Net | 16.00M | as of 2025-12-31 |
| Unrecognized Tax Benefits | 424.00M | as of 2025-12-31 |
| Unrecognized Tax Benefits, Increase Resulting from Prior Period Tax Positions | 106.00M | 2025-01-01 → 2025-12-31 |
| Unrecognized Tax Benefits, Decrease Resulting from Prior Period Tax Positions | 0 | 2025-01-01 → 2025-12-31 |
| Unrecognized Tax Benefits, Increase Resulting from Current Period Tax Positions | 0 | 2025-01-01 → 2025-12-31 |
| Unrecognized Tax Benefits, Decrease Resulting from Settlements with Taxing Authorities | 66.00M | 2025-01-01 → 2025-12-31 |
| Unrecognized Tax Benefits, Reduction Resulting from Lapse of Applicable Statute of Limitations | 40.00M | 2025-01-01 → 2025-12-31 |
| AociLiabilityForFuturePolicyBenefitExpectedFuturePolicyBenefitBeforeTax | 20.00M | as of 2025-12-31 |
| Unrecognized Tax Benefits that Would Impact Effective Tax Rate | 325.00M | as of 2025-12-31 |
| Lessor, Operating Lease, Payments to be Received | 298.00M | as of 2025-12-31 |
| Income (Loss) from Continuing Operations before Income Taxes, Domestic | 1.33B | 2025-01-01 → 2025-12-31 |
| Income (Loss) from Continuing Operations before Income Taxes, Foreign | 801.00M | 2025-01-01 → 2025-12-31 |
| Other Receivables, Net, Current | 7.90B | as of 2025-12-31 |
| Transfer to (from) Policyholder Account Balance (to) from Separate Account | -8.00M | 2025-01-01 → 2025-12-31 |
| Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value | 204.00M | as of 2025-12-31 |
| Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings | 33.00M | 2025-01-01 → 2025-12-31 |
| Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss) | -2.00M | 2025-01-01 → 2025-12-31 |
| Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases | 134.00M | 2025-01-01 → 2025-12-31 |
| Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales | 39.00M | 2025-01-01 → 2025-12-31 |
| Federal Home Loan Bank, Advances, General Debt Obligations, Maximum Amount Available | 1.30B | as of 2025-12-31 |
| Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net | -86.00M | 2025-01-01 → 2025-12-31 |
| Separate Account, Liability, Cash Surrender Value, Amount | 933.00M | as of 2025-12-31 |
| Separate Account, Liability, Premium and Deposit | 888.00M | 2025-01-01 → 2025-12-31 |
| Separate Account, Liability, Surrender and Withdrawal | 1.34B | 2025-01-01 → 2025-12-31 |
| SeparateAccountLiabilityBenefitPayment | 953.00M | 2025-01-01 → 2025-12-31 |
| SeparateAccountLiabilityIncreaseDecreaseFromInvestedPerformance | 84.00M | 2025-01-01 → 2025-12-31 |
| SeparateAccountLiabilityIncreaseDecreaseFromOtherChange | -8.00M | 2025-01-01 → 2025-12-31 |
| Fair Value, Asset, Recurring Basis, Still Held, Unrealized Gain (Loss), OCI | 0 | 2025-01-01 → 2025-12-31 |
| DebtSecuritiesAvailableForSaleAmortizedCostAfterAllowanceForCreditLoss | 28.60B | as of 2025-12-31 |
| Statutory Accounting Practices, Statutory Capital and Surplus Required | 11.71B | as of 2025-12-31 |
| Statutory Accounting Practices, Statutory Amount Available for Dividend Payments without Regulatory Approval | 3.79B | as of 2025-12-31 |
| Assets Held by Insurance Regulators | 737.00M | as of 2025-12-31 |