Derivative Instruments (Outstanding Derivative Instruments With Off-Balance-Sheet Risks) (Details) - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Outstanding derivative instruments with off-balance-sheet risks
Notional Amounts	$ 193,377
Interest rate contracts [Member]
Outstanding derivative instruments with off-balance-sheet risks
Notional Amounts	130,056
Foreign currency contracts [Member]
Outstanding derivative instruments with off-balance-sheet risks
Notional Amounts	3,085
Equity market contracts [Member]
Outstanding derivative instruments with off-balance-sheet risks
Notional Amounts	60,177
Credit contracts [Member]
Outstanding derivative instruments with off-balance-sheet risks
Notional Amounts	59
Total Derivative Instruments [Member]
Outstanding derivative instruments with off-balance-sheet risks
Notional Amounts	193,377	$ 161,115
Asset Fair Value	8,109	4,261
Liability Fair Value	7,527	4,621
Derivative investments [Member] | Interest rate contracts [Member] | Non-Qualifying Hedging [Member]
Outstanding derivative instruments with off-balance-sheet risks
Notional Amounts	128,298	112,921
Asset Fair Value	1,906	1,082
Liability Fair Value	154	219
Derivative investments [Member] | Foreign currency contracts [Member] | Non-Qualifying Hedging [Member]
Outstanding derivative instruments with off-balance-sheet risks
Notional Amounts	181	262
Asset Fair Value	9	1
Liability Fair Value		3
Derivative investments [Member] | Equity market contracts [Member] | Non-Qualifying Hedging [Member]
Outstanding derivative instruments with off-balance-sheet risks
Notional Amounts	60,177	43,283
Asset Fair Value	1,717	1,442
Liability Fair Value	1,357	664
Derivative investments [Member] | Credit contracts [Member] | Non-Qualifying Hedging [Member]
Outstanding derivative instruments with off-balance-sheet risks
Notional Amounts	59	55
Derivative investments [Member] | Cash Flow Hedges [Member] | Qualifying Hedges [Member]
Outstanding derivative instruments with off-balance-sheet risks
Notional Amounts	4,123	4,048
Asset Fair Value	732	299
Liability Fair Value	12	63
Derivative investments [Member] | Cash Flow Hedges [Member] | Interest rate contracts [Member] | Qualifying Hedges [Member]
Outstanding derivative instruments with off-balance-sheet risks
Notional Amounts	1,219	1,174
Asset Fair Value	245	108
Liability Fair Value		12
Derivative investments [Member] | Cash Flow Hedges [Member] | Foreign currency contracts [Member] | Qualifying Hedges [Member]
Outstanding derivative instruments with off-balance-sheet risks
Notional Amounts	2,904	2,874
Asset Fair Value	487	191
Liability Fair Value	12	51
Derivative investments [Member] | Fair Value Hedges [Member] | Interest rate contracts [Member] | Qualifying Hedges [Member]
Outstanding derivative instruments with off-balance-sheet risks
Notional Amounts	539	546
Liability Fair Value	323	202
Other Assets [Member] | GLB Direct Embedded Derivatives [Member] | Non-Qualifying Hedging [Member]
Outstanding derivative instruments with off-balance-sheet risks
Asset Fair Value		450
Liability Fair Value	3,086
Other Liabilities [Member] | GLB Ceded Embedded Derivatives [Member] | Non-Qualifying Hedging [Member]
Outstanding derivative instruments with off-balance-sheet risks
Asset Fair Value	3,081	60
Liability Fair Value		510
Reinsurance Related Embedded Derivatives [Member] | Embedded derivatives - Reinsurance related [Member] | Non-Qualifying Hedging [Member]
Outstanding derivative instruments with off-balance-sheet risks
Liability Fair Value	323	375
Future Contract Benefits [Member] | Indexed Annuity And IUL Contracts [Member] | Non-Qualifying Hedging [Member]
Outstanding derivative instruments with off-balance-sheet risks
Asset Fair Value	664	927
Liability Fair Value	$ 2,272	$ 2,585