Investments - Schedule of Rollforward of Credit Loss Allowance for Fixed Income Securities (Details) - USD ($) $ in Millions |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2026 |
Sep. 30, 2025 |
Sep. 30, 2026 |
Sep. 30, 2025 |
|
| Other than Temporary Impairment, Credit Losses Recognized in Earnings [Roll Forward] | ||||
| Ending balance | $ (11) | $ (5) | $ (11) | $ (5) |
| Fixed income securities | ||||
| Other than Temporary Impairment, Credit Losses Recognized in Earnings [Roll Forward] | ||||
| Beginning balance | (10) | (17) | (10) | (17) |
| Credit losses on securities for which credit losses not previously reported | 0 | 0 | 0 | (1) |
| Net (increases) decreases related to credit losses previously reported | (1) | 0 | (1) | 1 |
| Write-offs | 0 | 12 | 0 | 12 |
| Ending balance | (11) | (5) | (11) | (5) |
| Corporate bonds | ||||
| Other than Temporary Impairment, Credit Losses Recognized in Earnings [Roll Forward] | ||||
| Ending balance | (8) | (4) | (8) | (4) |
| ABS | ||||
| Other than Temporary Impairment, Credit Losses Recognized in Earnings [Roll Forward] | ||||
| Ending balance | $ (3) | $ (1) | $ (3) | $ (1) |