Investments - Components of Net Realized Gains and Losses (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Components of net realized capital gains (losses)
Sales of fixed maturity securities	$ (593)	$ (619)	$ (735)
Change in allowance for credit losses on loans			(25)
Net realized losses	(1,202)	(548)	(1,078)
Excluding Fortitude Re Funds Withheld Assets
Components of net realized capital gains (losses)
Net realized losses	(966)	(434)	(734)
Fortitude Re Funds Withheld Assets
Components of net realized capital gains (losses)
Net realized losses	(236)	(114)	(344)
Excluding modified coinsurance and funds withheld embedded derivative
Components of net realized capital gains (losses)
Sales of fixed maturity securities	(593)	(619)	(735)
Change in allowance for credit losses on fixed maturity securities	1	(25)	(44)
Foreign exchange transactions	163	247	129
All other derivatives and hedge accounting	(200)	(55)	(173)
Sales of alternative investments	3	(16)	29
Other	(411)	18	14
Net realized losses	(1,036)	(473)	(805)
Excluding modified coinsurance and funds withheld embedded derivative | Loans Receivable
Components of net realized capital gains (losses)
Change in allowance for credit losses on loans	1	(23)	(25)
Excluding modified coinsurance and funds withheld embedded derivative | Excluding Fortitude Re Funds Withheld Assets
Components of net realized capital gains (losses)
Sales of fixed maturity securities	(523)	(583)	(668)
Change in allowance for credit losses on fixed maturity securities	1	(25)	(44)
Foreign exchange transactions	146	256	124
All other derivatives and hedge accounting	(180)	(62)	(165)
Sales of alternative investments	3	(16)	29
Other	(403)	19	18
Net realized losses	(966)	(434)	(734)
Excluding modified coinsurance and funds withheld embedded derivative | Excluding Fortitude Re Funds Withheld Assets | Loans Receivable
Components of net realized capital gains (losses)
Change in allowance for credit losses on loans	(10)	(23)	(28)
Excluding modified coinsurance and funds withheld embedded derivative | Fortitude Re Funds Withheld Assets
Components of net realized capital gains (losses)
Sales of fixed maturity securities	(70)	(36)	(67)
Change in allowance for credit losses on fixed maturity securities	0	0	0
Foreign exchange transactions	17	(9)	5
All other derivatives and hedge accounting	(20)	7	(8)
Sales of alternative investments	0	0	0
Other	(8)	(1)	(4)
Net realized losses	(70)	(39)	(71)
Excluding modified coinsurance and funds withheld embedded derivative | Fortitude Re Funds Withheld Assets | Loans Receivable
Components of net realized capital gains (losses)
Change in allowance for credit losses on loans	11	0	3
Fortitude Re funds withheld embedded derivative
Components of net realized capital gains (losses)
Net realized losses	(166)	(75)	(273)
Fortitude Re funds withheld embedded derivative | Excluding Fortitude Re Funds Withheld Assets
Components of net realized capital gains (losses)
Net realized losses	0	0	0
Fortitude Re funds withheld embedded derivative | Fortitude Re Funds Withheld Assets
Components of net realized capital gains (losses)
Net realized losses	$ (166)	$ (75)	$ (273)