Future Policy Benefits Reserves - Narratives (Details) - USD ($) $ in Millions |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2026 |
Sep. 30, 2025 |
Sep. 30, 2026 |
Sep. 30, 2025 |
|
| Insurance [Abstract] | ||||
| Pretax change in LFPB | $ 173 | $ 7 | ||
| Liability for future policy benefit, expected future gross premium, discounted, before reinsurance | $ 3,100 | $ 3,600 | $ 3,100 | $ 3,600 |
| Liability for future policy benefit, weighted-average duration | 11 years | 11 years | 11 years | 11 years |
| Liability for future policy benefit, adverse development, expense | $ 218 | $ 65 | $ 267 | $ 93 |
| Liability future policy benefit, losses recognized in prior period | $ 1 | $ 43 | $ 13 | $ 54 |