Derivatives Instruments Level 4 Derivative Balance Sheet Classification (Details) - USD ($) $ in Millions	Jun. 30, 2017	Dec. 31, 2016
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Amount Not Offset Against Collateral	$ 780	$ 963
Derivative, Notional Amount	52,010	56,216
Derivative, Fair Value, Net	(514)	(1,001)
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement	1,277	976
Derivative Asset, Fair Value, Gross Asset	1,162	834
Derivative Asset, Fair Value, Gross Liability and Obligation to Return Cash, Offset	1,085	670
Derivative, Collateral, Obligation to Return Cash	(74)	(344)
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement	(1,791)	(1,977)
Derivative Asset, Fair Value of Collateral	41	103
Derivative Asset, Fair Value, Amount Offset Against Collateral	36	61
Derivative Liability, Fair Value, Gross Liability	(1,620)	(1,703)
Derivative Liability, Fair Value, Gross Asset and Right to Reclaim Cash, Offset	781	884
Derivative, Collateral, Right to Reclaim Cash	230	130
Derivative Liability, Fair Value of Collateral	827	763
Derivative Liability, Fair Value, Amount Offset Against Collateral	12	56
Other Policyholder Funds and Benefits Payable [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	12,228	13,164
Derivative, Fair Value, Net	(171)	(274)
Derivative Asset, Fair Value, Gross Asset	0	0
Derivative Liability, Fair Value, Gross Liability	(171)	(274)
Reinsurance Recoverable [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	3,416	3,584
Derivative, Fair Value, Net	115	141
Derivative Asset, Fair Value, Gross Asset	115	141
Derivative Liability, Fair Value, Gross Liability	0	0
Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	28,677	15,526
Derivative, Fair Value, Net	(609)	(689)
Derivative Asset, Fair Value, Gross Asset	991	457
Derivative Liability, Fair Value, Gross Liability	(1,600)	(1,146)
Other Investments [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	7,534	23,620
Derivative, Fair Value, Net	151	(180)
Derivative Asset, Fair Value, Gross Asset	171	377
Derivative Liability, Fair Value, Gross Liability	(20)	(557)
Fixed Maturities [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	155	322
Derivative, Fair Value, Net	0	1
Derivative Asset, Fair Value, Gross Asset	0	1
Derivative Liability, Fair Value, Gross Liability	0	0
Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	47,838	52,537
Derivative, Fair Value, Net	(498)	(907)
Derivative Asset, Fair Value, Gross Asset	1,188	954
Derivative Liability, Fair Value, Gross Liability	(1,686)	(1,861)
Put Option [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	0	500
Derivative, Fair Value, Net	0	1
Derivative Asset, Fair Value, Gross Asset	0	1
Derivative Liability, Fair Value, Gross Liability	0	0
Derivative Financial Instruments, Liabilities [Member] | Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets (Liabilities), at Fair Value, Net	(609)	(689)
Derivative Financial Instruments, Assets [Member] | Other Investments [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets (Liabilities), at Fair Value, Net	151	(180)
Foreign Exchange Contract [Member] | Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets (Liabilities), at Fair Value, Net	(267)	(237)
Foreign Exchange Contract [Member] | Other Investments [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets (Liabilities), at Fair Value, Net		27
Interest Rate Contract [Member] | Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets (Liabilities), at Fair Value, Net	(488)	(542)
Interest Rate Contract [Member] | Other Investments [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets (Liabilities), at Fair Value, Net	2	(427)
Interest Rate Contract [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	10,882	11,743
Derivative, Fair Value, Net	(485)	(890)
Derivative Asset, Fair Value, Gross Asset	643	264
Derivative Liability, Fair Value, Gross Liability	(1,128)	(1,154)
Interest Rate Contract [Member] | Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	3,873	3,440
Derivative, Fair Value, Net	(1)	(79)
Derivative Asset, Fair Value, Gross Asset	82	11
Derivative Liability, Fair Value, Gross Liability	(83)	(90)
Cash Flow Hedging [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	4,172	3,679
Derivative, Fair Value, Net	(16)	(94)
Derivative Asset, Fair Value, Gross Asset	89	22
Derivative Liability, Fair Value, Gross Liability	(105)	(116)
Currency Swap [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	165	1,064
Derivative, Fair Value, Net	0	68
Derivative Asset, Fair Value, Gross Asset	0	70
Derivative Liability, Fair Value, Gross Liability	0	(2)
Currency Swap [Member] | Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	299	239
Derivative, Fair Value, Net	(15)	(15)
Derivative Asset, Fair Value, Gross Asset	7	11
Derivative Liability, Fair Value, Gross Liability	(22)	(26)
Three Win Related Foreign Currency Swaps [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	804	804
Derivative, Fair Value, Net	(252)	(263)
Derivative Asset, Fair Value, Gross Asset	0	0
Derivative Liability, Fair Value, Gross Liability	(252)	(263)
Credit Default Swap, Buying Protection [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	115	209
Derivative, Fair Value, Net	(3)	(4)
Derivative Asset, Fair Value, Gross Asset	0	0
Derivative Liability, Fair Value, Gross Liability	(3)	(4)
Credit Default Swap, Selling Protection [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	1,654	1,309
Derivative, Fair Value, Net	2	10
Derivative Asset, Fair Value, Gross Asset	29	15
Derivative Liability, Fair Value, Gross Liability	(27)	(5)
Credit Derivatives in Offsetting Positions [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	1,934	3,317
Derivative, Fair Value, Net	3	(1)
Derivative Asset, Fair Value, Gross Asset	29	39
Derivative Liability, Fair Value, Gross Liability	(26)	(40)
Equity Contract [Member] | Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets (Liabilities), at Fair Value, Net	38	33
Equity Contract [Member] | Other Investments [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets (Liabilities), at Fair Value, Net	2
Equity Contract [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	321	105
Derivative, Fair Value, Net	3	0
Derivative Asset, Fair Value, Gross Asset	40	33
Derivative Liability, Fair Value, Gross Liability	(37)	(33)
Equity Contract [Member] | Fair Value Hedging [Member]
Derivatives, Fair Value [Line Items]
Derivative, Fair Value, Net	(35)	(27)
GMWB Product Derivatives [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	12,178	13,114
Derivative, Fair Value, Net	(134)	(241)
Derivative Asset, Fair Value, Gross Asset	0	0
Derivative Liability, Fair Value, Gross Liability	(134)	(241)
GMWB Reinsurance [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	2,527	2,709
Derivative, Fair Value, Net	57	73
Derivative Asset, Fair Value, Gross Asset	57	73
Derivative Liability, Fair Value, Gross Liability	0	0
GMWB Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	9,484	10,256
Derivative, Fair Value, Net	85	94
GMWB Hedging Instruments [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	9,484	10,256
Derivative, Fair Value, Net	85	94
Derivative Asset, Fair Value, Gross Asset	150	190
Derivative Liability, Fair Value, Gross Liability	(65)	(96)
Macro Hedge Program [Member] | Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets (Liabilities), at Fair Value, Net	74	50
Macro Hedge Program [Member] | Other Investments [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets (Liabilities), at Fair Value, Net	94	128
Macro Hedge Program [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	6,885	6,532
Derivative, Fair Value, Net	168	178
Derivative Asset, Fair Value, Gross Asset	182	201
Derivative Liability, Fair Value, Gross Liability	(14)	(23)
Coinsurance and Modified Coinsurance Reinsurance Contracts [Member]
Derivatives, Fair Value [Line Items]
Derivative, Fair Value, Net	58	68
Derivative Asset, Fair Value, Gross Asset	58	68
Derivative Liability, Fair Value, Gross Liability	0	0
Coinsurance and Modified Coinsurance Reinsurance Contracts [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Invested Assets Suppoting Modco	$ 889	$ 875