Investments - Realized Investment Gains and Losses (Details) - USD ($) $ in Millions |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2024 |
Sep. 30, 2023 |
Sep. 30, 2024 |
Sep. 30, 2023 |
|
| Investments [Abstract] | ||||
| Net realized investment gains (losses), excluding credit (loss)/recovery and other investment write-downs | $ 25 | $ (9) | $ 32 | $ (29) |
| Credit (loss)/recovery and other investment write-downs | (946) | (5) | (2,837) | (15) |
| Net realized investment (losses), before income taxes | $ (921) | $ (14) | $ (2,805) | $ (44) |