Investments (Invested Assets on Deposit, Held In Trust and Pledged as Collateral) (Details) - USD ($) $ in Millions |
Mar. 31, 2026 |
Dec. 31, 2025 |
|---|---|---|
| Investments, Debt and Equity Securities [Abstract] | ||
| Invested assets on deposit (regulatory deposits) | $ 6,559 | $ 6,570 |
| Invested assets held in trust (reinsurance agreements) | 6,955 | 7,268 |
| Invested assets pledged as collateral | 12,043 | 10,794 |
| Total invested assets on deposit, held in trust and pledged as collateral | $ 25,557 | $ 24,632 |