Investments (Continuous Gross Unrealized Losses for Fixed Maturity Securities by Sector) (Details) $ in Millions	Mar. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities in continuous unrealized loss position, less than 12 months, estimated fair value	$ 36,804	$ 16,729
Fixed maturity securities in continuous unrealized loss position, less than 12 months, gross unrealized losses	$ 1,957	$ 305
Fixed maturity securities in continuous unrealized loss position, less than 12 months, number of securities	5,202	2,423
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, estimated fair value	$ 4,073	$ 1,658
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, gross unrealized losses	$ 640	$ 145
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, number of securities	710	368
U.S. corporate
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities in continuous unrealized loss position, less than 12 months, estimated fair value	$ 14,235	$ 5,051
Fixed maturity securities in continuous unrealized loss position, less than 12 months, gross unrealized losses	884	111
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, estimated fair value	1,971	887
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, gross unrealized losses	317	76
Foreign corporate
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities in continuous unrealized loss position, less than 12 months, estimated fair value	5,532	2,016
Fixed maturity securities in continuous unrealized loss position, less than 12 months, gross unrealized losses	387	60
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, estimated fair value	555	305
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, gross unrealized losses	107	43
RMBS
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities in continuous unrealized loss position, less than 12 months, estimated fair value	4,934	3,481
Fixed maturity securities in continuous unrealized loss position, less than 12 months, gross unrealized losses	236	50
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, estimated fair value	410	32
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, gross unrealized losses	39	1
U.S. government and agency
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities in continuous unrealized loss position, less than 12 months, estimated fair value	2,845	1,712
Fixed maturity securities in continuous unrealized loss position, less than 12 months, gross unrealized losses	98	40
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, estimated fair value	574	222
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, gross unrealized losses	125	20
CMBS
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities in continuous unrealized loss position, less than 12 months, estimated fair value	4,077	1,390
Fixed maturity securities in continuous unrealized loss position, less than 12 months, gross unrealized losses	129	21
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, estimated fair value	391	95
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, gross unrealized losses	44	3
State and political subdivision
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities in continuous unrealized loss position, less than 12 months, estimated fair value	997	347
Fixed maturity securities in continuous unrealized loss position, less than 12 months, gross unrealized losses	97	6
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, estimated fair value	24	6
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, gross unrealized losses	4	0
ABS
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities in continuous unrealized loss position, less than 12 months, estimated fair value	3,732	2,454
Fixed maturity securities in continuous unrealized loss position, less than 12 months, gross unrealized losses	94	13
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, estimated fair value	148	93
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, gross unrealized losses	4	1
Foreign government
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities in continuous unrealized loss position, less than 12 months, estimated fair value	452	278
Fixed maturity securities in continuous unrealized loss position, less than 12 months, gross unrealized losses	32	4
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, estimated fair value	0	18
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, gross unrealized losses	$ 0	$ 1

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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