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Investments (Narrative) (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2025 | Jun. 30, 2024 | Jun. 30, 2025 | Jun. 30, 2024 | Dec. 31, 2024
Gain (Loss) on Securities [Line Items] |  |  |  |  |
Mortgage loan losses due to changes in expected credit losses | $ 5 | $ 0 | $ 5 | $ 0 |
Commitments to purchase or fund privately placed debt securities | 1,805 |  | 1,805 |  |
Commitments to sell various privately placed debt securities | 80 |  | 80 |  |
Fixed maturity securities |  |  |  |  |
Gain (Loss) on Securities [Line Items] |  |  |  |  |
Debt securities, available-for-sale, accrued interest, after allowance for credit loss | 451 | $ 444 | 451 | $ 444 | $ 442
Mortgage loans |  |  |  |  |
Gain (Loss) on Securities [Line Items] |  |  |  |  |
Financing receivable, accrued interest, after allowance for credit loss | $ 4 |  | $ 4 |  |

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