Separate Account Assets and Liabilities - Separate Account Liabilities (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2024	Dec. 31, 2023
Separate Account, Liability [Roll Forward]
Beginning balance	$ 77,457	$ 73,962
Premiums and deposits	338	1,488
Policy charges	(402)	(1,642)
Surrenders and other benefits	(1,936)	(6,472)
Investment return	4,318	9,897
Net transfer from (to) general account	5	67
Other charges	(27)	157
Ending balance	79,753	77,457
Cash surrender value	77,674	75,366
Variable Annuities
Separate Account, Liability [Roll Forward]
Beginning balance	65,839	63,223
Premiums and deposits	193	835
Policy charges	(326)	(1,343)
Surrenders and other benefits	(1,650)	(5,378)
Investment return	3,628	8,477
Net transfer from (to) general account	7	25
Other charges	0	0
Ending balance	67,691	65,839
Cash surrender value	66,167	64,280
Variable Universal Life
Separate Account, Liability [Roll Forward]
Beginning balance	8,795	7,653
Premiums and deposits	121	459
Policy charges	(75)	(292)
Surrenders and other benefits	(96)	(317)
Investment return	605	1,250
Net transfer from (to) general account	(2)	42
Other charges	0	0
Ending balance	9,348	8,795
Cash surrender value	8,793	8,263
Unitized Pooled Pension Funds
Separate Account, Liability [Roll Forward]
Beginning balance	2,823	3,086
Premiums and deposits	24	194
Policy charges	(1)	(7)
Surrenders and other benefits	(190)	(777)
Investment return	85	170
Net transfer from (to) general account	0	0
Other charges	(27)	157
Ending balance	2,714	2,823
Cash surrender value	$ 2,714	$ 2,823