Investments (Components of Net Investment Gains Losses - Transaction Type) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Gain (Loss) on Securities [Line Items]
Realized gains (losses) on investments sold or disposed	$ (195)	$ (20)	$ (330)	$ (566)
Impairment (losses)	0	(898)	0	(905)
Change in ACL recognized in earnings	(35)	(42)	(81)	(224)
Unrealized net gains (losses) recognized in earnings	(15)	16	17	54
Total recognized gains (losses)	(50)	(26)	(64)	(170)
Non-investment portfolio gains (losses)	(176)	(95)	(402)	(82)
Net investment gains (losses)	(421)	$ (1,039)	(796)	$ (1,723)
Private Equity Funds
Gain (Loss) on Securities [Line Items]
Realized gains (losses) on investments sold or disposed	3		46
Portfolio of investments, amount sold	57		798
Proceeds from sale of equity method investment	$ 54		$ 752

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