Future Contract Benefits - Summary of Changes in Present Values of Expected Net Premiums and LFPB (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024	Dec. 31, 2024	Dec. 31, 2023
Present Value of Expected LFPB
Net balance as of end-of-period	$ 40,665		$ 39,807
Payout Annuities
Present Value of Expected Net Premiums
Balance as of beginning-of-year	0	$ 0
Beginning balance at original discount rate	0	0
Effect of actual variances from expected experience			0	$ 0
Adjusted balance as of beginning-of-year	0	0
Issuances	0	0
Interest accrual	0	0
Net premiums collected	0	0
Flooring impact of LFPB	0	0
Ending balance at original discount rate	0	0
Effect of cumulative changes in discount rate assumptions	0	0
Balance as of end-of-period	0	0
Present Value of Expected LFPB
Balance as of beginning-of-year	2,009	2,085
Beginning balance at original discount rate	2,260	2,272
Effect of actual variances from expected experience			(1)	1
Adjusted balance as of beginning-of-year			2,259	2,273
Issuances	22	15
Interest accrual	22	22
Benefit payments	(49)	(49)
Ending balance at original discount rate	2,254	2,261
Effect of cumulative changes in discount rate assumptions	(221)	(227)
Balance as of end-of-period	2,033	2,034
Net balance as of end-of-period	2,033	2,034	2,009
Less: Reinsurance recoverables	1,478	1,562
Net balance as of end-of-period, net of reinsurance	$ 555	$ 472
Weighted-average duration of future policyholder benefit liability	9 years	9 years
Deferred profit liability	$ 65	$ 60
Payout Annuities | Cumulative Effect, Period of Adoption, Adjustment
Present Value of Expected Net Premiums
Balance as of beginning-of-year	0	0
Present Value of Expected LFPB
Balance as of beginning-of-year	(251)	(187)
Traditional Life
Present Value of Expected Net Premiums
Balance as of beginning-of-year	5,873	6,200
Beginning balance at original discount rate	6,148	6,348
Effect of actual variances from expected experience			(48)	2
Adjusted balance as of beginning-of-year	6,100	6,350
Issuances	64	108
Interest accrual	62	63
Net premiums collected	(192)	(202)
Flooring impact of LFPB	(5)	3
Ending balance at original discount rate	6,029	6,322
Effect of cumulative changes in discount rate assumptions	(196)	(254)
Balance as of end-of-period	5,833	6,068
Present Value of Expected LFPB
Balance as of beginning-of-year	9,647	10,041
Beginning balance at original discount rate	10,085	10,230
Effect of actual variances from expected experience			(55)	7
Adjusted balance as of beginning-of-year			10,030	$ 10,237
Issuances	64	108
Interest accrual	99	100
Benefit payments	(234)	(206)
Ending balance at original discount rate	9,959	10,239
Effect of cumulative changes in discount rate assumptions	(305)	(378)
Balance as of end-of-period	9,654	9,861
Net balance as of end-of-period	3,821	3,793	$ 3,774
Less: Reinsurance recoverables	360	421
Net balance as of end-of-period, net of reinsurance	$ 3,461	$ 3,372
Weighted-average duration of future policyholder benefit liability	9 years	9 years
Traditional Life | Cumulative Effect, Period of Adoption, Adjustment
Present Value of Expected Net Premiums
Balance as of beginning-of-year	$ (275)	$ (148)
Present Value of Expected LFPB
Balance as of beginning-of-year	$ (438)	$ (189)