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Investments (Narrative) (Details) - USD ($) | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2023 | Jun. 30, 2022 | Jun. 30, 2023 | Jun. 30, 2022 | Dec. 31, 2022
Gain (Loss) on Securities [Line Items] |  |  |  |  |
Mortgage loan losses due to changes in expected credit losses | $ 6,000,000 | $ 0 | $ 6,000,000 | $ 0 |
Commitments to purchase or fund privately placed debt securities | 1,480,000,000 |  | 1,480,000,000 |  |
Commitments to sell various privately placed debt securities | 60,000,000 |  | 60,000,000 |  |
Mortgage loans |  |  |  |  |
Gain (Loss) on Securities [Line Items] |  |  |  |  |
Financing receivable, accrued interest, after allowance for credit loss | 4,000,000 |  | 4,000,000 |  |
Fixed maturity securities |  |  |  |  |
Gain (Loss) on Securities [Line Items] |  |  |  |  |
Debt securities, available-for-sale, accrued interest, after allowance for credit loss | $ 413,000,000 | $ 374,000,000 | $ 413,000,000 | $ 374,000,000 | $ 394,000,000

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