Investments (Components of Net Investment Gains Losses - Transaction Type) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Gain (Loss) on Securities [Line Items]
Realized gains (losses) on investments sold or disposed	$ (145)	$ (195)	$ (446)	$ (330)
Impairment (losses)	2	0	7	0
Change in ACL recognized in earnings	(272)	(35)	(431)	(81)
Unrealized net gains (losses) recognized in earnings	59	(15)	73	17
Total recognized gains (losses)	(213)	(50)	(358)	(64)
Non-investment portfolio gains (losses)	87	(176)	151	(402)
Net investment gains (losses)	$ (273)	(421)	(660)	(796)
Private Equity Funds
Gain (Loss) on Securities [Line Items]
Realized gains (losses) on investments sold or disposed		3	2	46
Portfolio of investments, amount sold		57	43	798
Proceeds from sale of equity method investment		$ 54	$ 41	$ 752

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