Investments - Components of Net Realized Gains and Losses (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Components of net realized capital gains (losses)
Sales of fixed maturity securities	$ (169)	$ (95)	$ (270)	$ (459)
Net realized gains (losses)	(180)	(14)	(267)	(525)
Excluding Fortitude Re Funds Withheld Assets
Components of net realized capital gains (losses)
Net realized gains (losses)	(187)	(65)	(246)	(382)
Fortitude Re Funds Withheld Assets
Components of net realized capital gains (losses)
Net realized gains (losses)	7	51	(21)	(143)
Excluding modified coinsurance and funds withheld embedded derivative
Components of net realized capital gains (losses)
Sales of fixed maturity securities	(169)	(95)	(270)	(459)
Change in allowance for credit losses on fixed maturity securities	(18)	(30)	(19)	(24)
Foreign exchange transactions	52	125	108	160
All other derivatives and hedge accounting	(21)	(92)	(67)	(119)
Sales of alternative investments	4	0	13	1
Other	(27)	18	(12)	6
Net realized gains (losses)	(188)	(72)	(266)	(443)
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	(9)	2	(19)	(8)
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	(168)	(88)	(254)	(400)
Change in allowance for credit losses on fixed maturity securities	(18)	(30)	(19)	(24)
Foreign exchange transactions	52	123	111	155
All other derivatives and hedge accounting	(21)	(89)	(69)	(113)
Sales of alternative investments	4	0	14	1
Other	(24)	18	(9)	6
Net realized gains (losses)	(187)	(65)	(246)	(382)
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	(12)	1	(20)	(7)
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	(1)	(7)	(16)	(59)
Change in allowance for credit losses on fixed maturity securities	0	0	0	0
Foreign exchange transactions	0	2	(3)	5
All other derivatives and hedge accounting	0	(3)	2	(6)
Sales of alternative investments	0	0	(1)	0
Other	(3)	0	(3)	0
Net realized gains (losses)	(1)	(7)	(20)	(61)
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	3	1	1	(1)
Fortitude Re funds withheld embedded derivative
Components of net realized capital gains (losses)
Net realized gains (losses)	8	58	(1)	(82)
Fortitude Re funds withheld embedded derivative | Excluding Fortitude Re Funds Withheld Assets
Components of net realized capital gains (losses)
Net realized gains (losses)	0	0	0	0
Fortitude Re funds withheld embedded derivative | Fortitude Re Funds Withheld Assets
Components of net realized capital gains (losses)
Net realized gains (losses)	$ 8	$ 58	$ (1)	$ (82)