Separate Account (Summary of Balances and changes in Separate Account Liabilities) (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2023	Dec. 31, 2022
Separate Account, Liability [Line Items]
Balance as of beginning-of-year	$ 143,536
Balance as of end-of-period	148,421	$ 143,536
UL and Other [Member]
Separate Account, Liability [Line Items]
Balance as of beginning-of-year	20,920	24,785
Gross Deposit	394	1,900
Withdrawal	(75)	(454)
Policyholder assessments	(238)	(938)
Change in market performance	1,193	(4,371)
Net transfers from (to) general account	(32)	(2)
Balance as of end-of-period	22,162	20,920
Cash surrender value	19,863	18,666
Other Operations [Member]
Separate Account, Liability [Line Items]
Balance as of beginning-of-year	47
Balance as of end-of-period	49	47
Variable Annuities [Member]
Separate Account, Liability [Line Items]
Balance as of beginning-of-year	105,573	136,665
Gross Deposit	624	3,371
Withdrawal	(2,436)	(9,238)
Policyholder assessments	(624)	(2,603)
Change in market performance	5,054	(23,194)
Net transfers from (to) general account	143	572
Balance as of end-of-period	108,334	105,573
Cash surrender value	106,796	103,987
Retirement Plan Services Segment [Member]
Separate Account, Liability [Line Items]
Balance as of beginning-of-year	16,996	21,068
Gross Deposit	554	2,378
Withdrawal	(586)	(2,378)
Policyholder assessments	(40)	(164)
Change in market performance	978	(3,710)
Net transfers from (to) general account	(26)	(198)
Balance as of end-of-period	17,876	16,996
Cash surrender value	$ 17,862	$ 16,982