Investments and Derivative Instruments Level 4 Net Realized Capital Gains (Losses) (Details) - USD ($) $ in Millions		3 Months Ended				9 Months Ended
		Sep. 30, 2015		Sep. 30, 2014		Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Net Realized Capital Gains (Losses) [Line Items]
Available-for-sale Equity Securities, Amortized Cost Basis		$ 167				$ 167		$ 525
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss		93				93		142
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax		1,725				1,725		2,364
Available-for-sale Equity Securities, Accumulated Gross Unrealized Gain, before Tax		12				12		10
Available-for-sale Equity Securities, Accumulated Gross Unrealized Loss, before Tax		12				12		19
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss		245				245		208
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss		152				152		66
Net Realized Capital Gains (Losses) Table [Abstract]
Gain on Derivative Instruments, Pretax	[1]	33		$ 56		217	$ 218
Loss on Derivative Instruments, Pretax		33		8		181	203
Other than Temporary Impairment Losses, Investments, Portion Recognized in Earnings, Net		(24)		(10)		(32)	(20)
Periodic Net Coupon Settlements on Credit Derivatives		2		1		5	10
Gain (Loss) on Reinsurance Recoverables		0		0		0	579
Gain (Loss) on Coinsurance and Modified Coinsurance Reinsurance Contracts		3		8		29	402
Realized Investment Gains (Losses)		(22)		50		(18)	594
Gain (Loss) on Investments, Excluding Other than Temporary Impairments		2		60		14	614
Derivative, Gain (Loss) on Derivative, Net		22		(65)		(18)	822
Proceeds from Sale of Available-for-sale Securities		2,300		2,600		7,900	8,200
JAPAN
Net Realized Capital Gains (Losses) Table [Abstract]
Foreign Currency Transaction Gain (Loss), before Tax							2
Derivative, Gain (Loss) on Derivative, Net	[2]	0		0		0	(126)
UNITED STATES
Net Realized Capital Gains (Losses) Table [Abstract]
Derivative, Gain (Loss) on Derivative, Net		19		18		(11)	2
Fixed Annuity Hedging Instruments [Member] | JAPAN
Net Realized Capital Gains (Losses) Table [Abstract]
Change in Unrealized Gain (Loss) on Hedged Item in Foreign Currency Fair Value Hedge							(51)
Derivative, Gain (Loss) on Derivative, Net		0	[3]	0	[3]	0	22
Three Win Related Foreign Currency Swaps [Member] | JAPAN
Net Realized Capital Gains (Losses) Table [Abstract]
Change in Unrealized Gain (Loss) on Hedged Item in Foreign Currency Fair Value Hedge		(17)		83		(1)	38
Derivative, Gain (Loss) on Derivative, Net		0		0		0	(14)
Change in value of derivatives and Japan FVO securities [Member]
Net Realized Capital Gains (Losses) Table [Abstract]
Foreign Currency Transaction Gain (Loss), before Tax							37
Mortgages [Member]
Net Realized Capital Gains (Losses) Table [Abstract]
Valuation Allowances and Reserves, Adjustments		0		0
Accumulated Net Investment Gain (Loss) Attributable to Parent [Member]
Net Realized Capital Gains (Losses) Table [Abstract]
Gain (Loss) on Investments, Excluding Other than Temporary Impairments				37		10	(4)
Accumulated Net Investment Gain (Loss) Attributable to Parent [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Net Realized Capital Gains (Losses) Table [Abstract]
Gain (Loss) on Investments, Excluding Other than Temporary Impairments		(24)		37		10	(4)
Municipal Bonds [Member]
Net Realized Capital Gains (Losses) [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss		1				1		1
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss		9				9		1
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss		8				8		0
Asset-backed Securities [Member]
Net Realized Capital Gains (Losses) [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss		31				31		29
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax		22				22		20
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss		32				32		30
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss		1				1		1
Corporate Debt Securities [Member]
Net Realized Capital Gains (Losses) [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss		30				30		58
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax		1,174				1,174		1,685
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss		150				150		109
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss		120				120		51
Debt Securities [Member]
Net Realized Capital Gains (Losses) [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss		84				84		129
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss		233				233		189
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss		149				149		60
Equity Securities [Member]
Net Realized Capital Gains (Losses) [Line Items]
Available-for-sale Equity Securities, Amortized Cost Basis								275
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss		9				9		13
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss		12				12		19
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss		3				3		6
Foreign Government Debt Securities [Member]
Net Realized Capital Gains (Losses) [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss		3				3		4
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax		17				17		35
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss		11				11		9
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss		8				8		5
US States and Political Subdivisions Debt Securities [Member]
Net Realized Capital Gains (Losses) [Line Items]
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax		89				89		118
Residential Mortgage Backed Securities [Member]
Net Realized Capital Gains (Losses) [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss		9				9		11
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax		51				51		64
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss		10				10		12
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss		1				1		1
US Treasury Securities [Member]
Net Realized Capital Gains (Losses) [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss		0				0		1
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax		217				217		261
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss		1				1		1
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss		1				1		0
Collateralized Debt Obligations [Member]
Net Realized Capital Gains (Losses) [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	[4]	6				6		19
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax		77				77		84
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	[4]	8				8		20
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	[4]	2				2		1
Commercial Mortgage Backed Securities [Member]
Net Realized Capital Gains (Losses) [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss		4				4		6
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax		78				78		97
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss		12				12		7
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss		8				8		$ 1
Macro Hedge Program [Member] | UNITED STATES
Net Realized Capital Gains (Losses) Table [Abstract]
Derivative, Gain (Loss) on Derivative, Net						24	(13)
Variable Annuity [Member]
Net Realized Capital Gains (Losses) Table [Abstract]
Derivative, Gain (Loss) on Derivative, Net		19		18		(11)	(124)
Other Investments [Member]
Net Realized Capital Gains (Losses) Table [Abstract]
Realized Investment Gains (Losses)		$ (22)		$ (15)		(41)	(250)
Mortgages [Member]
Net Realized Capital Gains (Losses) Table [Abstract]
Valuation Allowances and Reserves, Adjustments						$ 4	$ 4

[1] Includes gains (losses) of $(51) for the nine months ended September 30, 2014 on transactional foreign currency re-valuation related to the Japan fixed annuity product. Also includes gains (losses) of $37 for the nine months ended September 30, 2014, due to change in value related to the derivative hedging instruments and the Japan government FVO securities.

[2] Other, net gains and losses include changes in value of non-qualifying derivatives, transactional foreign currency revaluation gains (losses) on yen denominated fixed payout annuity liabilities and gains (losses) on non-qualifying derivatives used to hedge the foreign currency exposure of the liabilities. Gains (losses) from transactional foreign currency revaluation of the reinsured liabilities were $(17) and $83, respectively, for the three months ended September 30, 2015 and 2014, and $(1) and $38, respectively, for the nine months ended September 30, 2015 and 2014. Gains (losses) on instruments used to hedge the foreign currency exposure on the reinsured fixed payout annuities were $8 and $(86), respectively, for the three months ended September 30, 2015 and 2014, and $(23) and $(58), respectively for the nine months ended September 30, 2015 and 2014.

[3] The associated liability is adjusted for changes in foreign exchange spot rates through realized capital gains and was $(51) for the nine months ended September 30, 2014

[4] Unrealized losses exclude the change in fair value of bifurcated embedded derivatives within certain securities, for which changes in fair value are recorded in net realized capital gains (losses).