Derivative Instruments Level 4 Derivative Balance Sheet Classification (Details) - USD ($) $ in Millions	Jun. 30, 2017	Dec. 31, 2016
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	$ 38,579	$ 41,099
Derivative, Fair Value, Net	(421)	(475)
Derivative Asset, Fair Value, Gross Asset	681	749
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement	796	890
Derivative Liability, Fair Value, Gross Liability	(1,046)	(1,091)
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement	1,217	1,365
Derivative, Fair Value, Amount Offset Against Collateral, Net [Abstract]
Derivative Asset, Fair Value, Gross Liability and Obligation to Return Cash, Offset	608	588
Derivative, Collateral, Obligation to Return Cash	65	74
Derivative Asset, Fair Value of Collateral	39	101
Derivative Asset, Fair Value, Amount Offset Against Collateral	34	60
Derivative Liability, Fair Value, Gross Asset and Right to Reclaim Cash, Offset	324	396
Derivative, Collateral, Right to Reclaim Cash	219	118
Derivative Liability, Fair Value of Collateral	721	655
Derivative Liability, Fair Value, Amount Offset Against Collateral	0	40
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	16,671	11,498
Derivative, Fair Value, Net	(503)	(577)
Derivative Asset, Fair Value, Gross Asset	536	424
Derivative Liability, Fair Value, Gross Liability	(1,039)	(1,001)
Other Investments [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	6,229	12,732
Derivative, Fair Value, Net	138	235
Derivative Asset, Fair Value, Gross Asset	145	325
Derivative Liability, Fair Value, Gross Liability	(7)	(90)
Fixed Maturities [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	35	121
Derivative, Fair Value, Net	0	0
Derivative Asset, Fair Value, Gross Asset	0	0
Derivative Liability, Fair Value, Gross Liability	0	0
Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	36,745	39,141
Derivative, Fair Value, Net	(410)	(466)
Derivative Asset, Fair Value, Gross Asset	781	871
Derivative Liability, Fair Value, Gross Liability	(1,191)	(1,337)
Currency Swap [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	37	382
Derivative, Fair Value, Net	0	36
Derivative Asset, Fair Value, Gross Asset	0	36
Derivative Liability, Fair Value, Gross Liability	0	0
Cash Flow Hedging [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	1,834	1,958
Derivative, Fair Value, Net	(11)	(9)
Derivative Asset, Fair Value, Gross Asset	15	19
Derivative Liability, Fair Value, Gross Liability	(26)	(28)
Derivative Financial Instruments, Liabilities [Member] | Other Liabilities [Member]
Derivative, Fair Value, Amount Offset Against Collateral, Net [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	(503)	(577)
Derivative Financial Instruments, Assets [Member] | Other Investments [Member]
Derivative, Fair Value, Amount Offset Against Collateral, Net [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	138	235
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	94	131
Derivative, Fair Value, Net	(4)	(3)
Derivative Asset, Fair Value, Gross Asset	0	0
Derivative Liability, Fair Value, Gross Liability	(4)	(3)
Credit Default Swap, Selling Protection [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	399	458
Derivative, Fair Value, Net	2	4
Derivative Asset, Fair Value, Gross Asset	7	5
Derivative Liability, Fair Value, Gross Liability	(5)	(1)
Credit Derivatives in Offsetting Positions [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	648	1,006
Derivative, Fair Value, Net	2	(1)
Derivative Asset, Fair Value, Gross Asset	12	16
Derivative Liability, Fair Value, Gross Liability	(10)	(17)
Equity Contract [Member] | Other Liabilities [Member]
Derivative, Fair Value, Amount Offset Against Collateral, Net [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	37
Equity Contract [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	100	100
Derivative, Fair Value, Net	0	0
Derivative Asset, Fair Value, Gross Asset	37	33
Derivative Liability, Fair Value, Gross Liability	(37)	(33)
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
Coinsurance and Modified Coinsurance Reinsurance Contracts [Member] | Not Designated as Hedging Instrument [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
Invested Assets Suppoting Modco	889	875
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)
Interest Rate Contract [Member] | Other Liabilities [Member]
Derivative, Fair Value, Amount Offset Against Collateral, Net [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	(391)
Interest Rate Contract [Member] | Other Investments [Member]
Derivative, Fair Value, Amount Offset Against Collateral, Net [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	0	30
Interest Rate Contract [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	2,700	2,774
Derivative, Fair Value, Net	(392)	(411)
Derivative Asset, Fair Value, Gross Asset	278	249
Derivative Liability, Fair Value, Gross Liability	(670)	(660)
Foreign Exchange Contract [Member] | Other Liabilities [Member]
Derivative, Fair Value, Amount Offset Against Collateral, Net [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	(264)
Foreign Exchange Contract [Member] | Other Investments [Member]
Derivative, Fair Value, Amount Offset Against Collateral, Net [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	0	4
Foreign Exchange Contract [Member] | Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative, Fair Value, Net	(12)
Macro Hedge Program [Member] | Other Liabilities [Member]
Derivative, Fair Value, Amount Offset Against Collateral, Net [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	74	50
Macro Hedge Program [Member] | Other Investments [Member]
Derivative, Fair Value, Amount Offset Against Collateral, Net [Abstract]
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)
Fair Value Hedging [Member] | Equity Contract [Member]
Derivatives, Fair Value [Line Items]
Derivative, Fair Value, Net	(35)	(27)
Cash Flow Hedging [Member] | Interest Rate Contract [Member] | Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	1,656	1,794
Derivative, Fair Value, Net	1	7
Derivative Asset, Fair Value, Gross Asset	8	9
Derivative Liability, Fair Value, Gross Liability	(7)	(2)
Cash Flow Hedging [Member] | Foreign Exchange Contract [Member] | Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	178	164
Derivative, Fair Value, Net		(16)
Derivative Asset, Fair Value, Gross Asset	7	10
Derivative Liability, Fair Value, Gross Liability	$ (19)	$ (26)