| Current Federal Tax Expense (Benefit) | 187.00M | 2025-01-01 → 2025-12-31 |
| Current State and Local Tax Expense (Benefit) | 68.00M | 2025-01-01 → 2025-12-31 |
| Current Foreign Tax Expense (Benefit) | 37.00M | 2025-01-01 → 2025-12-31 |
| Current Income Tax Expense (Benefit) | 292.00M | 2025-01-01 → 2025-12-31 |
| Deferred Federal Income Tax Expense (Benefit) | 38.00M | 2025-01-01 → 2025-12-31 |
| Deferred State and Local Income Tax Expense (Benefit) | 5.00M | 2025-01-01 → 2025-12-31 |
| Deferred Foreign Income Tax Expense (Benefit) | -31.00M | 2025-01-01 → 2025-12-31 |
| Operating Lease, Liability, Current | 62.00M | as of 2025-12-31 |
| Other Accrued Liabilities, Current | 48.00M | as of 2025-12-31 |
| Accrued Bonuses, Current | 312.00M | as of 2025-12-31 |
| Accrued Employee Benefits, Current | 174.00M | as of 2025-12-31 |
| Effective Income Tax Rate Reconciliation at Federal Statutory Income Tax Rate, Amount | 288.00M | 2025-01-01 → 2025-12-31 |
| Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Amount | 54.00M | 2025-01-01 → 2025-12-31 |
| EffectiveIncomeTaxRateReconciliationCrossBorderTaxEffectAmount | 4.00M | 2025-01-01 → 2025-12-31 |
| Long-term Debt, Fair Value | 7.00B | as of 2025-12-31 |
| Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount | 223.00M | as of 2025-12-31 |
| Business Combination, Consideration Transferred, Equity Interests Issued and Issuable | 634.00M | 2025-01-01 → 2025-12-31 |
| Effective Income Tax Rate Reconciliation, Nondeductible Expense, Amount | -14.00M | 2025-01-01 → 2025-12-31 |
| Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Prepaid Expense and Other Assets | 851.00M | as of 2025-12-31 |
| Effective Income Tax Rate Reconciliation, Tax Contingency, Amount | 5.00M | 2025-01-01 → 2025-12-31 |
| Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Noncurrent Assets | 127.00M | as of 2025-12-31 |
| Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets | 12.98B | as of 2025-12-31 |
| Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Other | 776.00M | as of 2025-12-31 |
| Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities | 80.00M | as of 2025-12-31 |
| Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Other | 288.00M | as of 2025-12-31 |
| Effective Income Tax Rate Reconciliation, Other Adjustments, Amount | -3.00M | 2025-01-01 → 2025-12-31 |
| Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities | 2.87B | as of 2025-12-31 |
| Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net | 10.11B | as of 2025-12-31 |
| Finite-Lived Intangible Asset, Expected Amortization, Year One | 450.00M | as of 2025-12-31 |
| Finite-Lived Intangible Asset, Expected Amortization, Year Two | 431.00M | as of 2025-12-31 |
| Finite-Lived Intangible Asset, Expected Amortization, Year Three | 424.00M | as of 2025-12-31 |
| Finite-Lived Intangible Asset, Expected Amortization, Year Four | 406.00M | as of 2025-12-31 |
| Finite-Lived Intangible Asset, Expected Amortization, Year Five | 395.00M | as of 2025-12-31 |
| Treasury Stock, Value, Acquired, Cost Method | 100.00M | 2025-01-01 → 2025-12-31 |
| Net Income (Loss) Available to Common Stockholders, Diluted | 989.00M | 2025-01-01 → 2025-12-31 |
| Stock Repurchase Program, Remaining Authorized Repurchase Amount | 1.40B | as of 2025-12-31 |
| Reinsurance Recoverable for Unpaid Claims and Claims Adjustments | 167.00M | as of 2025-12-31 |
| Defined Benefit Plan, Plan Assets, Contributions by Employer | 65.00M | 2025-01-01 → 2025-12-31 |
| Stock Issued During Period, Value, New Issues | 4.32B | 2025-01-01 → 2025-12-31 |
| Goodwill, Acquired During Period | 6.89B | 2025-01-01 → 2025-12-31 |
| Goodwill, Written off Related to Sale of Business Unit | 5.00M | 2025-01-01 → 2025-12-31 |
| Goodwill, Foreign Currency Translation Gain (Loss) | 237.00M | 2025-01-01 → 2025-12-31 |
| Goodwill, Purchase Accounting Adjustments | -2.00M | 2025-01-01 → 2025-12-31 |
| Business Acquisition, Goodwill, Expected Tax Deductible Amount | 1.93B | as of 2025-12-31 |
| Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Employee Compensation | 123.00M | as of 2025-12-31 |
| Operating Lease, Cost | 68.00M | 2025-01-01 → 2025-12-31 |
| Goodwill, Impaired, Accumulated Impairment Loss | 0 | as of 2025-12-31 |
| Short-term Lease, Cost | 1.00M | 2025-01-01 → 2025-12-31 |
| Variable Lease, Cost | 6.00M | 2025-01-01 → 2025-12-31 |
| Lease, Cost | 74.00M | 2025-01-01 → 2025-12-31 |
| Right-of-Use Asset Obtained in Exchange for Operating Lease Liability | 42.00M | 2025-01-01 → 2025-12-31 |
| Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value | 7.00M | 2025-01-01 → 2025-12-31 |
| Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals | 60.00M | as of 2025-12-31 |
| Business Acquisition, Pro Forma Revenue | 6.95B | 2025-01-01 → 2025-12-31 |
| Lessee, Operating Lease, Liability, to be Paid, Year One | 72.00M | as of 2025-12-31 |
| Business Acquisition, Pro Forma Net Income (Loss) | 1.22B | 2025-01-01 → 2025-12-31 |
| Lessee, Operating Lease, Liability, to be Paid, Year Two | 67.00M | as of 2025-12-31 |
| Lessee, Operating Lease, Liability, to be Paid, Year Three | 54.00M | as of 2025-12-31 |
| Lessee, Operating Lease, Liability, to be Paid, Year Four | 42.00M | as of 2025-12-31 |
| Lessee, Operating Lease, Liability, to be Paid, Year Five | 32.00M | as of 2025-12-31 |
| Lessee, Operating Lease, Liability, to be Paid, after Year Five | 73.00M | as of 2025-12-31 |
| Lessee, Operating Lease, Liability, to be Paid | 340.00M | as of 2025-12-31 |
| Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual | 747.00M | 2025-01-01 → 2025-12-31 |
| Deferred Tax Assets, Valuation Allowance | 2.00M | as of 2025-12-31 |
| Deferred Tax Assets, Net of Valuation Allowance | 662.00M | as of 2025-12-31 |
| Lessee, Operating Lease, Liability, Undiscounted Excess Amount | 35.00M | as of 2025-12-31 |
| Long-term Debt, Gross | 7.03B | as of 2025-12-31 |
| Goodwill, Fair Value Disclosure | 6.88B | as of 2025-12-31 |
| Deferred Tax Liabilities, Property, Plant and Equipment | 27.00M | as of 2025-12-31 |
| Insurance Commissions and Fees | 5.76B | 2025-01-01 → 2025-12-31 |
| Deferred Tax Liabilities, Intangible Assets | 1.35B | as of 2025-12-31 |
| Deferred Tax Liabilities, Net | 815.00M | as of 2025-12-31 |
| Long-Term Debt, Maturity, Year One | 719.00M | as of 2025-12-31 |
| Long-Term Debt, Maturity, Year Two | 313.00M | as of 2025-12-31 |
| Long-Term Debt, Maturity, Year Three | 500.00M | as of 2025-12-31 |
| Long-Term Debt, Maturity, Year Four | 350.00M | as of 2025-12-31 |
| Long-Term Debt, Maturity, Year Five | 800.00M | as of 2025-12-31 |
| Long-Term Debt, Maturity, after Year Five | 5.00B | as of 2025-12-31 |
| Debt Instrument, Unamortized Discount | 18.00M | as of 2025-12-31 |
| Debt Issuance Costs, Gross | 51.00M | as of 2025-12-31 |
| Unrecognized Tax Benefits | 18.00M | as of 2025-12-31 |
| Unrecognized Tax Benefits, Increase Resulting from Prior Period Tax Positions | 14.00M | 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, Decrease Resulting from Settlements with Taxing Authorities | 0 | 2025-01-01 → 2025-12-31 |
| Unrecognized Tax Benefits that Would Impact Effective Tax Rate | 18.00M | as of 2025-12-31 |