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Investments (Narrative) (Details) - USD ($) $ in Millions | Mar. 31, 2023 | Dec. 31, 2022 | Mar. 31, 2022
--- | --- | --- | ---
Gain (Loss) on Securities [Line Items] |  |  |
Commitments to purchase or fund privately placed debt securities | $ 1,665 |  |
Commitments to sell various privately placed debt securities | 125 |  |
Mortgage loans |  |  |
Gain (Loss) on Securities [Line Items] |  |  |
Financing receivable, accrued interest, after allowance for credit loss | 4 |  |
Fixed maturity securities |  |  |
Gain (Loss) on Securities [Line Items] |  |  |
Debt securities, available-for-sale, accrued interest, after allowance for credit loss | $ 407 | $ 394 | $ 389

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