Future Policy Benefits Reserves - Schedule of Balances and Changes (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Present value of future net premiums
Balance, January 1		$ 3,991	$ 4,735	$ 5,086
Effect of changes in discount rate	$ (125)	(74)	(880)	(1,140)
Balance, January 1, at original locked in discount rate	3,917	3,855	3,946
Effect of changes in cash flow assumptions		28	352	173
Expect of actual variances from expected experience		(126)	(49)	(24)
Adjusted balance, January 1		3,819	4,158	4,095
Interest accrual	202	216	219
Net premiums: earned during period	(436)	(457)	(459)
Balance, end of period at original locked in discount rate	3,585	3,917	3,855
Effect of changes in discount rate	(125)	(74)	(880)	(1,140)
Balance, December 31	3,710	3,991	4,735
Present value of future benefits & expenses
Balance, January 1		17,471	22,745	23,955
Effect of changes in discount rate	(578)	(125)	(5,942)	(7,395)
Balance, January 1, at original locked in discount rate	17,346	16,803	16,560
Effect of changes in cash flow assumptions		36	538	176
Effect of actual variances from expected experience		(46)	(21)	(19)
Adjusted balance, January 1		17,336	17,320	16,717
Interest accrual	962	979	973
Benefit & expense payments	(1,207)	(953)	(887)
Balance, end of period at original locked in discount rate	17,091	17,346	16,803
Effect of changes in discount rate	578	125	5,942	7,395
Balance, December 31	17,669	17,471	22,745
Net LFPB	13,959	13,480	18,010	$ 19,132
Re-measurement loss of insurance claims and policyholders’ benefits	$ (88)	$ (214)	$ (8)