Fair Value Measurements Level 4 Fair Value Option (Details) - USD ($) $ in Millions		3 Months Ended				6 Months Ended
		Jun. 30, 2016		Jun. 30, 2015		Jun. 30, 2016		Jun. 30, 2015		Mar. 31, 2016		Dec. 31, 2015		Mar. 31, 2015	Dec. 31, 2014
Fair Value, Option, Quantitative Disclosures [Line Items]
Changes in fair value of assets and liabilities accounted for using the fair value option		$ 2		$ (4)		$ (32)		$ 1
Fair value of assets accounted for using fair value option		123				123						$ 165
Credit Linked Notes [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Changes in fair value of assets and liabilities accounted for using the fair value option						(34)		2
Fixed Maturities [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Changes in fair value of assets and liabilities accounted for using the fair value option		2		(6)		2		(1)
Asset-backed Securities [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair value of assets accounted for using fair value option		0				0						4
Corporate Debt Securities [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Changes in fair value of assets and liabilities accounted for using the fair value option		0		(2)		0		1
Fair value of assets accounted for using fair value option		0				0						31
Collateralized Debt Obligations [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Changes in fair value of assets and liabilities accounted for using the fair value option		0		0		0		1
Fair value of assets accounted for using fair value option		0				0						1
Commercial Mortgage Backed Securities [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair value of assets accounted for using fair value option		0				0						6
Foreign Government Debt Securities [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Changes in fair value of assets and liabilities accounted for using the fair value option		0		0		0		0
Fair value of assets accounted for using fair value option		0				0						1
Residential Mortgage Backed Securities [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Changes in fair value of assets and liabilities accounted for using the fair value option		2		(4)		2		(3)
Fair value of assets accounted for using fair value option		123				123						119
US Treasury and Government [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair value of assets accounted for using fair value option		0				0						3
Equity Securities [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Changes in fair value of assets and liabilities accounted for using the fair value option		0		2
Fair value of assets accounted for using fair value option		0				0						281
Fair Value, Inputs, Level 3 [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value		171		286		171		286		$ 154		139		$ 137	$ 112
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss)				1		7	[1]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases		22		222		61		260
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements		3		5		9		10
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales		6		19		16		25
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3	[2]	3		5		6		6
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	[2]	2		53		17		57
Fair Value, Inputs, Level 3 [Member] | Derivative [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Change in Unrealized Gain (Loss)		7		(51)	[3],[4]	8	[3],[4],[5]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis with Unobservable Inputs		273	[5]	267		273	[5]	267				253	[5]	315
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Gain (Loss) Included in Earnings	[3],[6],[7]			(61)	[1]	8	[5]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Purchases				(2)		8	[5]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Settlements				(1)		(2)	[5]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Transfers out of Level 3	[2]			10		6	[5]
Available-for-sale Securities [Member] | Fair Value, Inputs, Level 3 [Member] | Equity Securities [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value		42		44		42		44		36		38		48	48
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss)		4				4		(2)	[1]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases		2		1		2		3
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements	[5]							0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales				8	[5]	2		8	[5]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	[2]			3				3
Credit Risk Contract [Member] | Fair Value, Inputs, Level 3 [Member] | Derivative [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Change in Unrealized Gain (Loss)	[3],[4]							3
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis with Unobservable Inputs				0				0						(6)	(3)
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Gain (Loss) Included in Earnings	[3],[6],[7]			(2)	[1]			1
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Purchases				(2)				(8)
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Settlements	[5]							0
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Sales	[5]			0				0
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Transfers out of Level 3	[2]			10				10
Commodity Contract [Member] | Fair Value, Inputs, Level 3 [Member] | Derivative [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Change in Unrealized Gain (Loss)	[3],[4]			(4)				(4)
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis with Unobservable Inputs				2				2						0	0
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Gain (Loss) Included in Earnings	[3],[6],[7]			(4)	[1]			(4)
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Settlements	[5]							0
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Sales				0				0	[5]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Transfers into Level 3	[2]			6				6
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Transfers out of Level 3	[2]			0
Equity Contract [Member] | Fair Value, Inputs, Level 3 [Member] | Derivative [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Change in Unrealized Gain (Loss)		(2)				(7)	[3],[4]	1	[3],[4]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis with Unobservable Inputs		1		3		1		3		3		0		5	5
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Gain (Loss) Included in Earnings	[3],[6],[7]	(2)		(2)	[1]	(7)		8
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Purchases						8
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Settlements	[5]							(10)
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Sales	[5]			0				0
Interest Rate Contract [Member] | Fair Value, Inputs, Level 3 [Member] | Derivative [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Change in Unrealized Gain (Loss)		(2)		3	[3],[4]	(5)	[3],[4]	(2)	[3],[4]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis with Unobservable Inputs		(34)		(28)		(34)		(28)		(32)		(29)		(30)	(27)
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Gain (Loss) Included in Earnings	[3],[6],[7]	(2)		3	[1]	(5)
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Settlements				(1)				(1)	[5]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Sales	[5]			0				0
Other Contract [Member] | Fair Value, Inputs, Level 3 [Member] | Derivative [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Change in Unrealized Gain (Loss)	[3],[4]							(33)
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis with Unobservable Inputs		273	[5]	267		273	[5]	267		260	[5]				286
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Gain (Loss) Included in Earnings	[3],[6],[7]	7	[5]					(43)
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Purchases								39
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Settlements	[5]							(31)
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Sales	[5]			0				0
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Transfers into Level 3	[2]			6				6
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Transfers out of Level 3	[2]	6	[5]					10
UNITED STATES | US GMWB Hedging Instruments [Member] | Fair Value, Inputs, Level 3 [Member] | Derivative [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Change in Unrealized Gain (Loss)		15		(32)	[3],[4]	24	[3],[4]	(16)	[3],[4]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis with Unobservable Inputs		165		125		165		125		144		135		159	170
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Gain (Loss) Included in Earnings	[3],[6],[7]	15		(34)	[1]	24		(25)
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Settlements	[5]							(20)
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Sales	[5]			0				0
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Transfers out of Level 3	[2]	6				6
UNITED STATES | US Macro Hedge Program [Member] | Fair Value, Inputs, Level 3 [Member] | Derivative [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Change in Unrealized Gain (Loss)		(4)		(18)	[3],[4]	(4)	[3],[4]	(15)	[3],[4]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis with Unobservable Inputs		141		165		141		165		$ 145		$ 147		$ 187	$ 141
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Gain (Loss) Included in Earnings	[3],[6],[7]	$ (4)		(22)	[1]	(4)		(23)
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Purchases								47
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Settlements						$ (2)		0	[5]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Sales	[5]			$ 0				$ 0

[1] [3]All amounts are before income taxes and amortization of DAC.

[2] [4]Transfers in and/or (out) of Level 3 are primarily attributable to the availability of market observable information and the re-evaluation of the observability of pricing inputs.

[3] 2]All amounts in these rows are reported in net realized capital gains (losses). The realized/unrealized gains (losses) included in net income for separate account assets are offset by an equal amount for separate account liabilities, which results in a net zero impact on net income for the Company. All amounts are before income taxes and amortization of DAC.

[4] [7]Amounts presented are for Level 3 only and therefore may not agree to other disclosures included herein.

[5] [5]Derivative instruments are reported in this table on a net basis for asset/(liability) positions and reported in the Condensed Consolidated Balance Sheet in other investments and other liabilities.

[6] [1]The Company classifies realized and unrealized gains and losses on GMWB reinsurance derivatives and GMWB embedded derivatives as unrealized gains (losses) for purposes of disclosure in this table because it is impracticable to track on a contract-by-contract basis the realized gains (losses) for these derivatives and embedded derivatives.

[7] [6]Includes both market and non-market impacts in deriving realized and unrealized gains (losses).