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Investments (Components of Net Investment Gains Losses - Transaction Type) (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2024 | Sep. 30, 2023 | Sep. 30, 2024 | Sep. 30, 2023
Gain (Loss) on Securities [Line Items] |  |  |  |
Realized gains (losses) on investments sold or disposed | $ (39) | $ (281) | $ (369) | $ (847)
Impairment (losses) | (17) | (591) | (17) | (1,496)
Change in ACL recognized in earnings | (150) | 25 | (231) | (199)
Unrealized net gains (losses) recognized in earnings | (59) | (17) | (42) | 37
Total recognized gains (losses) | (209) | 8 | (273) | (162)
Non-investment portfolio gains (losses) | 188 | (63) | (214) | (145)
Net investment gains (losses) | $ (77) | $ (927) | (873) | $ (2,650)
Private Equity Funds |  |  |  |
Gain (Loss) on Securities [Line Items] |  |  |  |
Realized gains (losses) on investments sold or disposed |  |  | 46 |
Portfolio of investments, amount sold |  |  | 798 |
Proceeds from sale of equity method investment |  |  | $ 752 |

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