Investments and Derivative Instruments Level 4 Derivative Balance Sheet Location (Details) - USD ($) $ in Millions		Dec. 31, 2015	Dec. 31, 2014
Derivative Balance Sheet Location [Line Items]
Derivative, Notional Amount		$ 46,241	$ 55,838
Derivative, Fair Value, Net		(530)	(460)
Derivative Asset, Fair Value, Gross Asset		852	959
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement		1,014	1,050
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement		(1,544)	(1,510)
Derivative Liability, Fair Value, Gross Liability		(1,255)	(1,345)
Fixed Maturities [Member]
Derivative Balance Sheet Location [Line Items]
Derivative Asset, Fair Value, Gross Asset		0	1
Not Designated as Hedging Instrument [Member]
Derivative Balance Sheet Location [Line Items]
Derivative, Notional Amount		44,309	53,421
Derivative, Fair Value, Net		(549)	(478)
Derivative Asset, Fair Value, Gross Asset		969	1,010
Derivative Liability, Fair Value, Gross Liability		(1,518)	(1,488)
Foreign Exchange Contract [Member] | Other Liabilities [Member]
Derivative Balance Sheet Location [Line Items]
Derivative Assets (Liabilities), at Fair Value, Net		376
Interest Rate Contract [Member] | Other Liabilities [Member]
Derivative Balance Sheet Location [Line Items]
Derivative Assets (Liabilities), at Fair Value, Net		431
Embedded Derivative Financial Instruments [Member] | Other Liabilities [Member]
Derivative Balance Sheet Location [Line Items]
Derivative Assets (Liabilities), at Fair Value, Net			3
Currency Swap [Member]
Derivative Balance Sheet Location [Line Items]
Derivative, Notional Amount		386	60
Derivative, Fair Value, Net		4	0
Derivative Asset, Fair Value, Gross Asset		4	0
Derivative Liability, Fair Value, Gross Liability		0	0
Reinsurance Recoverable [Member]
Derivative Balance Sheet Location [Line Items]
Derivative, Notional Amount		4,000	4,633
Derivative, Fair Value, Net		162	90
Derivative Asset, Fair Value, Gross Asset		162	90
Derivative Liability, Fair Value, Gross Liability		0	0
Other Investments [Member]
Derivative Balance Sheet Location [Line Items]
Derivative, Notional Amount		11,837	13,588
Derivative, Fair Value, Net		250	339
Derivative Asset, Fair Value, Gross Asset		360	478
Derivative Liability, Fair Value, Gross Liability		(110)	(139)
Cash Flow Hedging [Member]
Derivative Balance Sheet Location [Line Items]
Derivative, Notional Amount		1,909	2,385
Derivative, Fair Value, Net		19	18
Derivative Asset, Fair Value, Gross Asset		45	40
Derivative Liability, Fair Value, Gross Liability		(26)	(22)
Fair Value Hedging [Member]
Derivative Balance Sheet Location [Line Items]
Derivative, Notional Amount		23	32
Derivative, Fair Value, Net		0	0
Derivative Asset, Fair Value, Gross Asset		0	0
Derivative Liability, Fair Value, Gross Liability		0	0
Credit Derivatives in Offsetting Positions [Member]
Derivative Balance Sheet Location [Line Items]
Derivative, Notional Amount		1,435	2,175
Derivative, Fair Value, Net		(1)	(1)
Derivative Asset, Fair Value, Gross Asset		17	21
Derivative Liability, Fair Value, Gross Liability		(18)	(22)
Equity Contract [Member]
Derivative Balance Sheet Location [Line Items]
Derivative, Notional Amount		404	422
Derivative, Fair Value, Net		15	1
Derivative Asset, Fair Value, Gross Asset		41	30
Derivative Liability, Fair Value, Gross Liability		(26)	(29)
Coinsurance and Modified Coinsurance Reinsurance Contracts [Member]
Derivative Balance Sheet Location [Line Items]
Derivative, Notional Amount		895	974
Derivative, Fair Value, Net		79	34
Derivative Asset, Fair Value, Gross Asset		79	34
Derivative Liability, Fair Value, Gross Liability		0	0
Fixed Maturities [Member]
Derivative Balance Sheet Location [Line Items]
Derivative, Notional Amount		184	186
Derivative, Fair Value, Net		(1)	1
Derivative Liability, Fair Value, Gross Liability		(1)	0
Other Liabilities [Member]
Derivative Balance Sheet Location [Line Items]
Derivative, Notional Amount		15,071	19,473
Derivative, Fair Value, Net		(653)	(725)
Derivative Asset, Fair Value, Gross Asset		492	481
Derivative Liability, Fair Value, Gross Liability		(1,145)	(1,206)
Other Policyholder Funds and Benefits Payable [Member]
Derivative Balance Sheet Location [Line Items]
Derivative, Notional Amount		15,149	17,958
Derivative, Fair Value, Net		(288)	(165)
Derivative Asset, Fair Value, Gross Asset		0	0
Derivative Liability, Fair Value, Gross Liability		(288)	(165)
Interest Rate Contract [Member] | Not Designated as Hedging Instrument [Member]
Derivative Balance Sheet Location [Line Items]
Derivative, Notional Amount		4,710	4,857
Derivative, Fair Value, Net		(415)	(323)
Derivative Asset, Fair Value, Gross Asset		285	385
Derivative Liability, Fair Value, Gross Liability		(700)	(708)
Credit Default Swap, Buying Protection [Member]
Derivative Balance Sheet Location [Line Items]
Derivative, Notional Amount		249	276
Derivative, Fair Value, Net		10	(1)
Derivative Asset, Fair Value, Gross Asset		12	4
Derivative Liability, Fair Value, Gross Liability		(2)	(5)
Credit Default Swap, Selling Protection [Member]
Derivative Balance Sheet Location [Line Items]
Derivative, Notional Amount	[1]	1,435	946
Derivative, Fair Value, Net	[1]	(10)	7
Derivative Asset, Fair Value, Gross Asset	[1]	5	11
Derivative Liability, Fair Value, Gross Liability	[1]	(15)	(4)
JAPAN | Three Win Related Foreign Currency Swaps [Member]
Derivative Balance Sheet Location [Line Items]
Derivative, Notional Amount		1,063	1,319
Derivative, Fair Value, Net		(357)	(427)
Derivative Asset, Fair Value, Gross Asset		0	0
Derivative Liability, Fair Value, Gross Liability		(357)	(427)
UNITED STATES | GMWB Hedging Instruments [Member]
Derivative Balance Sheet Location [Line Items]
Derivative, Notional Amount		10,979	14,442
Derivative, Fair Value, Net		158	174
Derivative Asset, Fair Value, Gross Asset		264	289
Derivative Liability, Fair Value, Gross Liability		(106)	(115)
UNITED STATES | Macro Hedge Program [Member]
Derivative Balance Sheet Location [Line Items]
Derivative, Notional Amount		4,548	6,383
Derivative, Fair Value, Net		147	141
Derivative Asset, Fair Value, Gross Asset		179	180
Derivative Liability, Fair Value, Gross Liability		(32)	(39)
UNITED STATES | Other Contract [Member] | GMWB Hedging Instruments [Member]
Derivative Balance Sheet Location [Line Items]
Derivative, Notional Amount		5,877	7,041
Derivative, Fair Value, Net		131	124
UNITED STATES | Equity Contract [Member] | GMWB Hedging Instruments [Member]
Derivative Balance Sheet Location [Line Items]
Derivative, Notional Amount		1,362	3,761
Derivative, Fair Value, Net		2	39
UNITED STATES | GMWB Product Derivatives [Member]
Derivative Balance Sheet Location [Line Items]
Derivative, Notional Amount	[2]	15,099	17,908
Derivative, Fair Value, Net	[2]	(262)	(139)
Derivative Asset, Fair Value, Gross Asset	[2]	0	0
Derivative Liability, Fair Value, Gross Liability	[2]	(262)	(139)
UNITED STATES | GMWB Reinsurance [Member]
Derivative Balance Sheet Location [Line Items]
Derivative, Notional Amount		3,106	3,659
Derivative, Fair Value, Net		83	56
Derivative Asset, Fair Value, Gross Asset		83	56
Derivative Liability, Fair Value, Gross Liability		0	0
UNITED STATES | Interest Rate Contract [Member] | GMWB Hedging Instruments [Member]
Derivative Balance Sheet Location [Line Items]
Derivative, Notional Amount		3,740	3,640
Derivative, Fair Value, Net		25	11
Cash Flow Hedging [Member] | Foreign Exchange Contract [Member] | Designated as Hedging Instrument [Member]
Derivative Balance Sheet Location [Line Items]
Derivative, Notional Amount		143	143
Derivative, Fair Value, Net		7	(19)
Derivative Asset, Fair Value, Gross Asset			3
Derivative Liability, Fair Value, Gross Liability		(26)	(22)
Cash Flow Hedging [Member] | Interest Rate Contract [Member] | Designated as Hedging Instrument [Member]
Derivative Balance Sheet Location [Line Items]
Derivative, Notional Amount		1,766	2,242
Derivative, Fair Value, Net		38	37
Derivative Asset, Fair Value, Gross Asset		38	37
Derivative Liability, Fair Value, Gross Liability		$ 0	$ 0

[1] The derivative instruments related to this strategy are held for other investment purposes.

[2] These derivatives are embedded within liabilities and are not held for risk management purposes.