Fair Value Measurements Level 4 Credit Standing Adjustments and Behavior Risk Margins (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative, Gain (Loss) on Derivative, Net	[1]	$ (104)	$ (353)	$ (125)
Credit standing adjustment asset (liability), net		0	1
Credit standing adjustment assumption net of reinsurance [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative, Gain (Loss) on Derivative, Net		(2)	3	(13)
Gain (Loss) Due to Changes in Assumptions [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative, Gain (Loss) on Derivative, Net		(42)	31	75
GMWB Derivatives, Net [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Behavior Risk Margin		45	74
GMWB Derivatives, Net [Member] | Behavior Risk Margin Update Due to Underlying Fund Performance [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative, Gain (Loss) on Derivative, Net		$ (18)	$ 5	$ 33

[1] [3]Excludes investments that contain an embedded credit derivative for which the Company has elected the fair value option. For further discussion, see the Fair Value Option section in Note 4 - Fair Value Measurements.