Investments - Funds Held Directly Managed (Details) - USD ($) $ in Millions |
3 Months Ended | |
|---|---|---|
Mar. 31, 2025 |
Dec. 31, 2024 |
|
| Investments, Debt and Equity Securities [Abstract] | ||
| Funds held - directly managed, at cost | $ 2,460 | $ 2,587 |
| Accumulated change in fair value - embedded derivative accounting | (107) | (141) |
| Funds held - directly managed, at fair value | 2,353 | $ 2,446 |
| Funds held - directly managed, period increase (decrease) | $ (93) |