Investments (Components of Net Investment Gains Losses - Transaction Type) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Gain (Loss) on Securities [Line Items]
Realized gains (losses) on investments sold or disposed	$ (301)	$ (135)
Impairment (losses)	5	0
Change in ACL recognized in earnings	(159)	(46)
Unrealized net gains (losses) recognized in earnings	14	32
Total recognized gains (losses)	(145)	(14)
Non-investment portfolio gains (losses)	64	(226)
Net investment gains (losses)	(387)	(375)
Private Equity Funds
Gain (Loss) on Securities [Line Items]
Realized gains (losses) on investments sold or disposed	2	43
Portfolio of investments, amount sold	43	741
Proceeds from sale of equity method investment	$ 41	$ 698

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