Investments (ACL for Fixed Maturity Securities AFS By Sector) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Debt Securities, Available-for-sale, Allowance for Credit Loss [Line Items]
Allowance, beginning of period	$ 99	$ 177	$ 81	$ 0
ACL not previously recorded	18	0	54	215
Changes for securities with previously recorded ACL	(2)	(2)	(8)	(13)
Securities sold or exchanged	(32)	(100)	(44)	(126)
Securities intended/required to be sold prior to recovery of amortized cost basis	0	0	0	(1)
Disposition	(2)	0	(2)	0
Write-offs	(13)	0	(13)	0
Allowance, end of period	68	75	68	75
U.S. corporate
Debt Securities, Available-for-sale, Allowance for Credit Loss [Line Items]
Allowance, beginning of period	39	30	44	0
ACL not previously recorded	18	0	18	58
Changes for securities with previously recorded ACL	0	4	3	(3)
Securities sold or exchanged	(26)	(4)	(34)	(24)
Securities intended/required to be sold prior to recovery of amortized cost basis	0	0	0	(1)
Disposition	0	0	0	0
Write-offs	(13)	0	(13)	0
Allowance, end of period	18	30	18	30
Foreign government
Debt Securities, Available-for-sale, Allowance for Credit Loss [Line Items]
Allowance, beginning of period	21	129	21	0
ACL not previously recorded	0	0	0	139
Changes for securities with previously recorded ACL	0	(4)	0	(8)
Securities sold or exchanged	0	(96)	0	(102)
Securities intended/required to be sold prior to recovery of amortized cost basis	0	0	0	0
Disposition	(2)	0	(2)	0
Write-offs	0	0	0	0
Allowance, end of period	19	29	19	29
Foreign corporate
Debt Securities, Available-for-sale, Allowance for Credit Loss [Line Items]
Allowance, beginning of period	32	16	16	0
ACL not previously recorded	0	0	25	16
Changes for securities with previously recorded ACL	(2)	0	(7)	0
Securities sold or exchanged	(6)	0	(10)	0
Securities intended/required to be sold prior to recovery of amortized cost basis	0	0	0	0
Disposition	0	0	0	0
Write-offs	0	0	0	0
Allowance, end of period	24	16	24	16
RMBS
Debt Securities, Available-for-sale, Allowance for Credit Loss [Line Items]
Allowance, beginning of period	0	2	0	0
ACL not previously recorded	0	0	0	2
Changes for securities with previously recorded ACL	0	(2)	0	(2)
Securities sold or exchanged	0	0	0	0
Securities intended/required to be sold prior to recovery of amortized cost basis	0	0	0	0
Disposition	0	0	0	0
Write-offs	0	0	0	0
Allowance, end of period	0	0	0	0
CMBS
Debt Securities, Available-for-sale, Allowance for Credit Loss [Line Items]
Allowance, beginning of period	7	0	0	0
ACL not previously recorded	0	0	11	0
Changes for securities with previously recorded ACL	0	0	(4)	0
Securities sold or exchanged	0	0	0	0
Securities intended/required to be sold prior to recovery of amortized cost basis	0	0	0	0
Disposition	0	0	0	0
Write-offs	0	0	0	0
Allowance, end of period	$ 7	$ 0	$ 7	$ 0