Derivative Instruments Derivative Instruments (Hedged Item Offset By Derivatives Achieving Fair Value Hedge Accounting) (Details) (Details) - USD ($) $ in Millions		Dec. 31, 2019	Dec. 31, 2018
Derivative [Line Items]
Fixed maturities, available-for-sale:	[1]	$ 391,096	$ 353,656
Commercial mortgage and other loans	[1]	63,559	59,830
Policyholders’ account balances		(152,110)	(150,338)
Future policy benefits		(293,527)	$ (273,846)
Carrying Amount of the Hedged Assets (Liabilities)
Derivative [Line Items]
Fixed maturities, available-for-sale:		389
Commercial mortgage and other loans		23
Policyholders’ account balances		(1,376)
Future policy benefits		(676)
Cumulative Adjustment Included in Carrying Amount
Derivative [Line Items]
Fixed maturities, available-for-sale:		64
Commercial mortgage and other loans		2
Policyholders’ account balances		(107)
Future policy benefits		$ (172)

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