Investments - Components of Net Investment Income (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Net Investment Income [Line Items]
Total investment income	$ 4,434	$ 3,681	$ 2,550
Investment expenses	179	235	180
Net investment income	4,255	3,446	2,370
Change in fair value of equity method investment	586	53	29
Excluding Fortitude Re Funds Withheld Assets
Net Investment Income [Line Items]
Total investment income	4,290	3,501	2,497
Investment expenses	179	235	180
Net investment income	4,111	3,266	2,317
Fortitude Re Funds Withheld Assets
Net Investment Income [Line Items]
Total investment income	144	180	53
Investment expenses	0	0
Net investment income	144	180	53
Corebridge Financial Inc
Net Investment Income [Line Items]
Dividend income	162
Change in fair value of equity method investment	439
Available for sale fixed maturity securities, including short-term investments
Net Investment Income [Line Items]
Total investment income	3,078	2,957	2,073
Available for sale fixed maturity securities, including short-term investments \| Excluding Fortitude Re Funds Withheld Assets
Net Investment Income [Line Items]
Total investment income	2,989	2,862	1,960
Available for sale fixed maturity securities, including short-term investments \| Fortitude Re Funds Withheld Assets
Net Investment Income [Line Items]
Total investment income	89	95	113
Other fixed maturity securities
Net Investment Income [Line Items]
Total investment income	19	46	(374)
Gains/(losses) recognized in earnings on hedging derivatives			(195)
Other fixed maturity securities \| Excluding Fortitude Re Funds Withheld Assets
Net Investment Income [Line Items]
Total investment income	0	3	(282)
Other fixed maturity securities \| Fortitude Re Funds Withheld Assets
Net Investment Income [Line Items]
Total investment income	19	43	(92)
Equity securities
Net Investment Income [Line Items]
Total investment income	149	53	29
Equity securities \| Excluding Fortitude Re Funds Withheld Assets
Net Investment Income [Line Items]
Total investment income	149	53	29
Equity securities \| Fortitude Re Funds Withheld Assets
Net Investment Income [Line Items]
Total investment income	0	0
Interest on mortgage and other loans
Net Investment Income [Line Items]
Total investment income	261	321	291
Interest on mortgage and other loans \| Excluding Fortitude Re Funds Withheld Assets
Net Investment Income [Line Items]
Total investment income	229	283	264
Interest on mortgage and other loans \| Fortitude Re Funds Withheld Assets
Net Investment Income [Line Items]
Total investment income	32	38	27
Alternative investments
Net Investment Income [Line Items]
Total investment income	196	199	315
Alternative investments \| Excluding Fortitude Re Funds Withheld Assets
Net Investment Income [Line Items]
Total investment income	196	199	315
Alternative investments \| Fortitude Re Funds Withheld Assets
Net Investment Income [Line Items]
Total investment income	0	0
Other investments
Net Investment Income [Line Items]
Total investment income	731	105	216
Gains/(losses) recognized in earnings on hedging derivatives			186
Other investments \| Excluding Fortitude Re Funds Withheld Assets
Net Investment Income [Line Items]
Total investment income	727	101	211
Other investments \| Fortitude Re Funds Withheld Assets
Net Investment Income [Line Items]
Total investment income	$ 4	$ 4	$ 5

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Amount, after investment expense, of income earned from investments in securities and real estate. Includes, but is not limited to, real estate investment, policy loans, dividends, and interest. Excludes realized gain (loss) on investments.

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