Derivative Instruments (Hedged Item Offset By Derivatives Achieving Fair Value Hedge Accounting) (Details) - USD ($) $ in Millions		Jun. 30, 2021	Dec. 31, 2020
Derivative [Line Items]
Fixed maturities, available-for-sale	[1]	$ 382,981	$ 412,905
Commercial mortgage and other loans	[1]	64,359	65,425
Policyholders’ account balances		(159,548)	(161,682)
Future policy benefits		(289,233)	(306,343)
Carrying Amount of the Hedged Assets (Liabilities)
Derivative [Line Items]
Fixed maturities, available-for-sale		372	402
Commercial mortgage and other loans		19	20
Policyholders’ account balances		(1,545)	(1,627)
Future policy benefits		(1,511)	(1,585)
Cumulative Adjustment Included in Carrying Amount
Derivative [Line Items]
Fixed maturities, available-for-sale		67	79
Commercial mortgage and other loans		1	2
Policyholders’ account balances		(193)	(303)
Future policy benefits		$ (294)	$ (372)

[1] See Note 4 for details of balances associated with variable interest entities.