Insurance and Contractholder Liabilities - Summary of Market Risk Benefit (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023
Insurance Loss Reserves [Abstract]
Annuitization election period	30 days
Market Risk Benefit [Roll Forward]
Balance, beginning of year	$ 1,003	$ 1,268
Balance, beginning of year, before the effect of nonperformance risk (own credit risk)	1,085	1,379
Changes due to expected run-off	(6)	(14)
Changes due to capital markets versus expected	(133)	(194)
Changes due to policyholder behavior versus expected	(17)	8
Assumption changes	0	(32)
Balance, end of period, before the effect of changes in nonperformance risk (own credit risk)	929	1,147
Nonperformance risk (own credit risk), end of period	(64)	(78)
Balance, end of period	865	1,069
Reinsured market risk benefit, end of period	$ 927	$ 1,143