Future Contract Benefits - Summary of Changes in Present Values of Expected Net Premiums and LFPB (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023	Dec. 31, 2022
Present Value of Expected LFPB
Net balance as of end-of-period	$ 38,889		$ 40,174
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	2,084	2,003
Beginning balance of original discount rate	2,271	2,266
Effect of actual variances from expected experience			3	(2)
Adjusted balance as of beginning-of-year	2,274	2,264
Issuances	39	69
Interest accrual	43	43
Benefit payments	(98)	(93)
Ending balance at original discount rate	2,258	2,283
Effect of cumulative changes in discount rate assumptions	(257)	(236)
Balance as of end-of-period	2,001	2,047
Net balance as of end-of-period	2,001	2,047	2,084
Less: reinsurance recoverables (2)	1,527	10
Net balance as of end-of-period, net of reinsurance	$ 474	$ 2,037
Weighted-average duration of future policyholder benefit liability (years)	9 years	9 years
Deferred profit liability	$ 61	$ 53
Payout Annuities | Cumulative effect from adoption of new accounting standards
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	(187)	(263)
Traditional Life
Present Value of Expected Net Premiums
Balance as of beginning-of-year	6,084	5,896
Beginning balance at original discount rate	6,236	6,480
Effect of actual variances from expected experience			(10)	(257)
Adjusted balance as of beginning-of-year			6,226	6,223
Issuances	206	330
Interest accrual	122	116
Net premiums collected	(396)	(395)
Flooring impact of LFPB	2	3
Ending balance at original discount rate	6,160	6,277
Effect of cumulative changes in discount rate assumptions	(322)	(329)
Balance as of end-of-period	5,838	5,948
Present Value of Expected LFPB
Balance as of beginning-of-year	9,637	9,086
Beginning balance of original discount rate	9,839	9,879
Effect of actual variances from expected experience			(15)	$ (280)
Adjusted balance as of beginning-of-year	9,824	9,599
Issuances	206	330
Interest accrual	190	179
Benefit payments	(357)	(309)
Ending balance at original discount rate	9,863	9,799
Effect of cumulative changes in discount rate assumptions	(511)	(479)
Balance as of end-of-period	9,352	9,320
Net balance as of end-of-period	3,514	3,372	$ 3,553
Less: reinsurance recoverables (2)	232	263
Net balance as of end-of-period, net of reinsurance	$ 3,282	$ 3,109
Weighted-average duration of future policyholder benefit liability (years)	10 years	10 years
Traditional Life | Cumulative effect from adoption of new accounting standards
Present Value of Expected Net Premiums
Balance as of beginning-of-year	$ (152)	$ (584)
Present Value of Expected LFPB
Balance as of beginning-of-year	$ (202)	$ (793)