Future Contract Benefits - Summary of Changes in Present Values of LFPB (UL and Other) (Details) - UL and Other - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Present Value of Expected LFPB
Balance as of beginning-of-year	$ 15,752	$ 14,777
Balance as of beginning-of-year, excluding shadow balance in AOCI	16,605	15,682
Effect of changes in cash flow assumptions		207	$ 165
Effect of actual variances from expected experience		288	$ (77)
Adjusted balance as of beginning-of-year	17,100	15,770
Interest accrual	841	765
Net assessments collected	1,288	658
Benefit payments	(1,051)	(588)
Balance as of end-of-year, excluding shadow balance in AOCI	18,178	16,605
Balance as of end-of-period	16,663	15,752
Less: reinsurance recoverables	10,748	9,505
Net balance as of end-of-period, net of reinsurance	$ 5,915	$ 6,247
Weighted-average duration of future policyholder benefit liability	16 years	17 years
Cumulative effect from adoption of new accounting standards
Present Value of Expected LFPB
Balance as of beginning-of-year	$ (853)	$ (905)
Balance as of end-of-period	$ (1,515)	$ (853)