Deferred Acquisition Costs - Rollforward of Deferred Acquisition Costs (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2024	Dec. 31, 2023
Movement Analysis of Deferred Policy Acquisition Costs [Roll Forward]
Balance, beginning of period	$ 12,302
Balance, end of period	12,173	$ 12,302
Other product lines, end of period	377	335
Total balance, end of period	12,173	12,302
Variable annuity
Movement Analysis of Deferred Policy Acquisition Costs [Roll Forward]
Balance, beginning of period	11,967	12,699
Deferrals of acquisition costs	98	394
Amortization	(269)	(1,126)
Balance, end of period	$ 11,796	$ 11,967