Derivative Instruments (Gains (Losses) On Derivative Instruments Recorded Within Income (Loss) From Continuing Operations) (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Gains (losses)
Gains (losses)		$ 710	$ (1,821)	$ (1,244)
Designated as Hedging Instrument [Member] | Cash Flow Hedges [Member]
Gains (losses)
Gains (losses)		31	31	24
Designated as Hedging Instrument [Member] | Fair Value Hedges [Member]
Gains (losses)
Gains (losses)		23	(16)	(12)
Designated as Hedging Instrument [Member] | Net Investment Income [Member] | Cash Flow Hedges [Member] | Interest rate contracts [Member]
Gains (losses)
Gains (losses)	[1]	4	4	5
Designated as Hedging Instrument [Member] | Net Investment Income [Member] | Cash Flow Hedges [Member] | Foreign currency contracts [Member]
Gains (losses)
Gains (losses)	[1]	27	18	11
Designated as Hedging Instrument [Member] | Net Investment Income [Member] | Fair Value Hedges [Member] | Interest rate contracts [Member]
Gains (losses)
Gains (losses)	[1]	(14)	(23)	(28)
Designated as Hedging Instrument [Member] | Realized Gain (Loss) [Member] | Cash Flow Hedges [Member] | Interest rate contracts [Member]
Gains (losses)
Gains (losses)	[2]			1
Designated as Hedging Instrument [Member] | Realized Gain (Loss) [Member] | Cash Flow Hedges [Member] | Foreign currency contracts [Member]
Gains (losses)
Gains (losses)	[2]		9	7
Designated as Hedging Instrument [Member] | Realized Gain (Loss) [Member] | Fair Value Hedges [Member] | Interest rate contracts [Member]
Gains (losses)
Gains (losses)	[2]	37	7	16
Derivative Instruments Not Designated and Not Qualifying as Hedging Instruments [Member] | Realized Gain (Loss) [Member] | Interest rate contracts [Member]
Gains (losses)
Gains (losses)	[2]	(149)	103	181
Derivative Instruments Not Designated and Not Qualifying as Hedging Instruments [Member] | Realized Gain (Loss) [Member] | Foreign currency contracts [Member]
Gains (losses)
Gains (losses)	[2]	5		(14)
Derivative Instruments Not Designated and Not Qualifying as Hedging Instruments [Member] | Realized Gain (Loss) [Member] | Equity market contracts [Member]
Gains (losses)
Gains (losses)	[2]	445	(1,427)	(1,253)
Derivative Instruments Not Designated and Not Qualifying as Hedging Instruments [Member] | Realized Gain (Loss) [Member] | GLB Direct And Ceded Embedded Derivative [Member]
Gains (losses)
Gains (losses)	[2]	(1)
Derivative Instruments Not Designated and Not Qualifying as Hedging Instruments [Member] | Realized Gain (Loss) [Member] | Embedded derivatives - Reinsurance related [Member]
Gains (losses)
Gains (losses)	[2]	292	(141)	(57)
Derivative Instruments Not Designated and Not Qualifying as Hedging Instruments [Member] | Realized Gain (Loss) [Member] | Indexed Annuity And Embedded Derivatives [Member]
Gains (losses)
Gains (losses)	[2]	81	(400)	(120)
Derivative Instruments Not Designated and Not Qualifying as Hedging Instruments [Member] | Commissions And Other Expenses [Member] | Equity market contracts [Member]
Gains (losses)
Gains (losses)	[3]	$ (17)	28	12
Derivative Instruments Not Designated and Not Qualifying as Hedging Instruments [Member] | Commissions And Other Expenses [Member] | Credit contracts [Member]
Gains (losses)
Gains (losses)	[3]		$ 1	$ (5)

[1] Reported in net investment income on our Consolidated Statements of Comprehensive Income (Loss).

[2] Reported in realized gain (loss) on our Consolidated Statements of Comprehensive Income (Loss).

[3] Reported in commissions and other expenses on our Consolidated Statements of Comprehensive Income (Loss).