Investments - Components of Net Investment Income (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Net Investment Income [Line Items]
Total investment income	$ 810	$ 1,018	$ 3,458	$ 3,077
Investment expenses	38	45	115	135
Net investment income	772	973	3,343	2,942
Change in fair value of equity method investment	(288)	25	393	172
Excluding Fortitude Re Funds Withheld Assets
Net Investment Income [Line Items]
Total investment income	781	967	3,350	2,954
Investment expenses	38	45	115	135
Net investment income	743	922	3,235	2,819
Fortitude Re Funds Withheld Assets
Net Investment Income [Line Items]
Total investment income	29	51	108	123
Investment expenses	0	0	0	0
Net investment income	29	51	108	123
Corebridge Financial Inc
Net Investment Income [Line Items]
Dividend income	20	65	78	133
Change in fair value of equity method investment	(348)	(35)	316	30
Available for sale fixed maturity securities, including short-term investments
Net Investment Income [Line Items]
Total investment income	886	771	2,590	2,301
Available for sale fixed maturity securities, including short-term investments \| Excluding Fortitude Re Funds Withheld Assets
Net Investment Income [Line Items]
Total investment income	873	746	2,539	2,234
Available for sale fixed maturity securities, including short-term investments \| Fortitude Re Funds Withheld Assets
Net Investment Income [Line Items]
Total investment income	13	25	51	67
Other fixed maturity securities
Net Investment Income [Line Items]
Total investment income	11	20	38	27
Other fixed maturity securities \| Excluding Fortitude Re Funds Withheld Assets
Net Investment Income [Line Items]
Total investment income	0	4	0	0
Other fixed maturity securities \| Fortitude Re Funds Withheld Assets
Net Investment Income [Line Items]
Total investment income	11	16	38	27
Equity securities
Net Investment Income [Line Items]
Total investment income	62	60	85	144
Equity securities \| Excluding Fortitude Re Funds Withheld Assets
Net Investment Income [Line Items]
Total investment income	62	60	85	144
Equity securities \| Fortitude Re Funds Withheld Assets
Net Investment Income [Line Items]
Total investment income	0	0	0	0
Interest on mortgage and other loans
Net Investment Income [Line Items]
Total investment income	46	61	150	211
Interest on mortgage and other loans \| Excluding Fortitude Re Funds Withheld Assets
Net Investment Income [Line Items]
Total investment income	40	52	130	185
Interest on mortgage and other loans \| Fortitude Re Funds Withheld Assets
Net Investment Income [Line Items]
Total investment income	6	9	20	26
Alternative investments
Net Investment Income [Line Items]
Total investment income	137	42	228	128
Alternative investments \| Excluding Fortitude Re Funds Withheld Assets
Net Investment Income [Line Items]
Total investment income	137	42	228	129
Alternative investments \| Fortitude Re Funds Withheld Assets
Net Investment Income [Line Items]
Total investment income	0	0	0	(1)
Other investments
Net Investment Income [Line Items]
Total investment income	(332)	64	367	266
Other investments \| Excluding Fortitude Re Funds Withheld Assets
Net Investment Income [Line Items]
Total investment income	(331)	63	368	262
Other investments \| Fortitude Re Funds Withheld Assets
Net Investment Income [Line Items]
Total investment income	$ (1)	$ 1	$ (1)	$ 4

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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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