Future Contract Benefits - Summary of Changes in Present Values of Expected Net Premiums and LFPB (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Present Value of Expected LFPB
Net balance as of end-of-year	$ 40,174	$ 38,302
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 changes in cash flow assumptions		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-year	0	0
Present Value of Expected LFPB
Balance as of beginning-of-year	2,003	2,511
Beginning balance of original discount rate	2,266	2,245
Effect of changes in cash flow assumptions		0	0
Effect of actual variances from expected experience		1	3
Adjusted balance as of beginning-of-year	2,267	2,248
Issuances	109	122
Interest accrual	86	84
Benefit payments	(191)	(188)
Ending balance of original discount rate	2,271	2,266
Effect of cumulative changes in discount rate assumptions	(187)	(263)
Balance as of end-of-year	2,084	2,003
Net balance as of end-of-year	2,084	2,003
Less: reinsurance recoverables	1,627	10
Net balance as of end-of-year, net of reinsurance	$ 457	$ 1,993
Weighted-average duration of future policyholder benefit liability	9 years	9 years
Deferred profit liability	$ 56	$ 38	22
Payout Annuities | Cumulative Effect, Period of Adoption, Adjustment
Present Value of Expected Net Premiums
Balance as of beginning-of-year	0	0
Balance as of end-of-year		0
Present Value of Expected LFPB
Balance as of beginning-of-year	(263)	266
Balance as of end-of-year		(263)
Traditional Life
Present Value of Expected Net Premiums
Balance as of beginning-of-year	5,896	6,610
Beginning balance at original discount rate	6,480	5,767
Effect of changes in cash flow assumptions		(5)	(382)
Effect of actual variances from expected experience		(275)	(21)
Adjusted balance as of beginning-of-year	6,200	5,364
Issuances	580	1,655
Interest accrual	236	209
Net premiums collected	(784)	(742)
Flooring impact of LFPB	4	(6)
Ending balance at original discount rate	6,236	6,480
Effect of cumulative changes in discount rate assumptions	(152)	(584)
Balance as of end-of-year	6,084	5,896
Present Value of Expected LFPB
Balance as of beginning-of-year	9,086	10,353
Beginning balance of original discount rate	9,879	8,893
Effect of changes in cash flow assumptions		(21)	(321)
Effect of actual variances from expected experience		(305)	(5)
Adjusted balance as of beginning-of-year	9,553	8,567
Issuances	580	1,655
Interest accrual	364	326
Benefit payments	(658)	(669)
Ending balance of original discount rate	9,839	9,879
Effect of cumulative changes in discount rate assumptions	(202)	(793)
Balance as of end-of-year	9,637	9,086
Net balance as of end-of-year	3,553	3,190
Less: reinsurance recoverables	255	270
Net balance as of end-of-year, net of reinsurance	$ 3,298	$ 2,920
Weighted-average duration of future policyholder benefit liability	10 years	11 years
Traditional Life | Cumulative Effect, Period of Adoption, Adjustment
Present Value of Expected Net Premiums
Balance as of beginning-of-year	$ (584)	$ 843
Balance as of end-of-year		(584)
Present Value of Expected LFPB
Balance as of beginning-of-year	(793)	1,460
Balance as of end-of-year		(793)
Group Protection
Present Value of Expected LFPB
Balance as of beginning-of-year	5,462	5,936
Beginning balance of original discount rate	6,059	5,674
Effect of changes in cash flow assumptions		(27)	15
Effect of actual variances from expected experience		(261)	(117)
Adjusted balance as of beginning-of-year	5,771	5,572
Issuances	1,702	1,777
Interest accrual	159	141
Benefit payments	(1,453)	(1,431)
Ending balance of original discount rate	6,179	6,059
Effect of cumulative changes in discount rate assumptions	(490)	(597)
Balance as of end-of-year	5,689	5,462
Net balance as of end-of-year	5,689	5,462
Less: reinsurance recoverables	123	127
Net balance as of end-of-year, net of reinsurance	$ 5,566	$ 5,335
Weighted-average duration of future policyholder benefit liability	5 years	4 years
Group Protection | Cumulative Effect, Period of Adoption, Adjustment
Present Value of Expected LFPB
Balance as of beginning-of-year	$ (597)	$ 262
Balance as of end-of-year		(597)
UL and Other
Present Value of Expected LFPB
Balance as of beginning-of-year	14,777	12,513
Balance as of beginning-of-year, excluding shadow balance in AOCI	15,682	11,400
Effect of changes in cash flow assumptions		165	3,108
Effect of actual variances from expected experience		(77)	$ 195
Adjusted balance as of beginning-of-year	15,770	14,703
Issuances	0	7
Interest accrual	765	626
Net assessments collected	658	974
Benefit payments	(588)	(628)
Balance as of end-of-year, excluding shadow balance in AOCI	16,605	15,682
Balance as of end-of-year	15,752	14,777
Net balance as of end-of-year	15,752	14,777
Less: reinsurance recoverables	9,505	1,975
Net balance as of end-of-year, net of reinsurance	$ 6,247	$ 12,802
Weighted-average duration of future policyholder benefit liability	17 years	17 years
UL and Other | Cumulative Effect, Period of Adoption, Adjustment
Present Value of Expected LFPB
Balance as of beginning-of-year	$ (905)	$ 1,113
Balance as of end-of-year	$ (853)	$ (905)