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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