Fair Value Measurements Level 4 Credit Standing Adjustments and Behavior Risk Margins (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative, Gain (Loss) on Derivative, Net	$ (353)	$ (125)	$ 105
Credit standing adjustment asset (liability), net	1	(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	3	(13)	(69)
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	31	75	274
GMWB Derivatives, Net [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Behavior Risk Margin	74	108
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	$ 5	$ 33	$ 106