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Investments (Components of Net Investment Gains Losses - Transaction Type) (Details) - USD ($) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2024 | Mar. 31, 2023
Gain (Loss) on Securities [Line Items] |  |
Realized gains (losses) on investments sold or disposed (1) | $ (135) | $ (546)
Impairment (losses) | 0 | (7)
Change in allowance for credit loss recognized in earnings | (46) | (182)
Unrealized net gains (losses) recognized in earnings | 32 | 38
Total recognized gains (losses) | (14) | (144)
Non-investment portfolio gains (losses) | (226) | 13
Net investment gains (losses) | (375) | (684)
Impairment (losses) | 0 | $ (7)
Private Equity Funds |  |
Gain (Loss) on Securities [Line Items] |  |
Realized gains (losses) on investments sold or disposed (1) | 43 |
Equity Method Investment, Amount Sold | 741 |
Proceeds from Sale of Equity Method Investments | $ 698 |

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