Insurance and Contractholder Liabilities - Summary of Market Risk Benefit (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Insurance Loss Reserves [Abstract]
Annuitization election period	30 days
Market Risk Benefit [Roll Forward]
Balance, beginning of year	$ 1,268	$ 1,824
Balance, beginning of year, before the effect of nonperformance risk (own credit risk)	1,379	1,949
Changes due to expected run-off	(19)	(54)
Changes due to capital markets versus expected	(254)	(567)
Changes due to policyholder behavior versus expected	(5)	(14)
Assumption changes	(16)	65
Balance, end of period, before the effect of changes in nonperformance risk (own credit risk)	1,085	1,379
Nonperformance risk (own credit risk), end of period	(82)	(111)
Balance, end of period	1,003	1,268
Reinsured market risk benefit, end of period	$ 1,081	$ 1,374