Insurance (Policyholder Account Balances) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Policyholder Account Balance [Line Items]
Interest credited	$ 422	$ 248
Policyholder Account Balance, Ending Balance	76,120	66,711
Universal Life Insurance
Policyholder Account Balance [Line Items]
Policyholder Account Balance, Beginning Balance	2,658	2,694
Premiums and deposits	55	55
Surrenders and withdrawals	(70)	(21)
Benefit payments	(25)	(20)
Net transfers from (to) separate account	12	15
Interest credited	22	4
Policy charges	(57)	(56)
Changes related to embedded derivatives	0	0
Policyholder Account Balance, Ending Balance	$ 2,595	$ 2,671
Weighted-average crediting rate (2)	0.84%	0.15%
Variable Annuities
Policyholder Account Balance [Line Items]
Policyholder Account Balance, Beginning Balance	$ 4,908	$ 4,743
Premiums and deposits	27	49
Surrenders and withdrawals	(177)	(131)
Benefit payments	(36)	(34)
Net transfers from (to) separate account	11	85
Interest credited	41	44
Policy charges	(7)	(7)
Changes related to embedded derivatives	0	0
Policyholder Account Balance, Ending Balance	$ 4,767	$ 4,749
Weighted-average crediting rate (2)	0.85%	0.93%
Index-linked Annuities
Policyholder Account Balance [Line Items]
Policyholder Account Balance, Beginning Balance	$ 33,896	$ 32,000
Premiums and deposits	1,677	1,594
Surrenders and withdrawals	(785)	(473)
Benefit payments	(50)	(36)
Net transfers from (to) separate account	0	0
Interest credited	96	71
Policy charges	(2)	(2)
Changes related to embedded derivatives	1,090	(756)
Policyholder Account Balance, Ending Balance	$ 35,922	$ 32,398
Weighted-average crediting rate (2)	0.32%	0.27%
Fixed Rate Annuities
Policyholder Account Balance [Line Items]
Policyholder Account Balance, Beginning Balance	$ 14,274	$ 11,849
Premiums and deposits	912	44
Surrenders and withdrawals	(506)	(155)
Benefit payments	(102)	(83)
Net transfers from (to) separate account	0	0
Interest credited	106	72
Policy charges	0	0
Changes related to embedded derivatives	0	0
Policyholder Account Balance, Ending Balance	$ 14,684	$ 11,727
Weighted-average crediting rate (2)	0.73%	0.61%
ULSG
Policyholder Account Balance [Line Items]
Policyholder Account Balance, Beginning Balance	$ 5,307	$ 5,569
Premiums and deposits	171	176
Surrenders and withdrawals	(6)	(10)
Benefit payments	(38)	(23)
Net transfers from (to) separate account	0	0
Interest credited	43	63
Policy charges	(258)	(263)
Changes related to embedded derivatives	0	0
Policyholder Account Balance, Ending Balance	$ 5,219	$ 5,512
Weighted-average crediting rate (2)	0.82%	1.14%
Company-Owned Life Insurance
Policyholder Account Balance [Line Items]
Policyholder Account Balance, Beginning Balance	$ 641	$ 646
Premiums and deposits	0	0
Surrenders and withdrawals	0	0
Benefit payments	(2)	(3)
Net transfers from (to) separate account	0	2
Interest credited	7	7
Policy charges	(2)	(2)
Changes related to embedded derivatives	0	0
Policyholder Account Balance, Ending Balance	$ 644	$ 650
Weighted-average crediting rate (2)	1.09%	0.93%

Amount of interest expense for allocation to policyholder account balance.

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