Fair Value Measurements (Details 2) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012		Sep. 30, 2011
Withdrawal Utilization [Member] | Level 3 [Member]
Fair Value Inputs [Abstract]
Positive or negative relationship of change in input to change in fair value measurement			Increase	[1],[2]
Withdrawal Utilization [Member] | Level 3 [Member] | Maximum [Member]
Fair Value Inputs [Abstract]
Range of Values-Unobservable Inputs			100.00%	[1]
Withdrawal Utilization [Member] | Level 3 [Member] | Minimum [Member]
Fair Value Inputs [Abstract]
Range of Values-Unobservable Inputs			20.00%	[1]
Withdrawal Rates [Member] | Level 3 [Member]
Fair Value Inputs [Abstract]
Positive or negative relationship of change in input to change in fair value measurement			Increase	[1],[2]
Withdrawal Rates [Member] | Level 3 [Member] | Maximum [Member]
Fair Value Inputs [Abstract]
Range of Values-Unobservable Inputs			8.00%	[1]
Withdrawal Rates [Member] | Level 3 [Member] | Minimum [Member]
Fair Value Inputs [Abstract]
Range of Values-Unobservable Inputs			0.00%	[1]
Lapse Rates [Member] | Level 3 [Member]
Fair Value Inputs [Abstract]
Positive or negative relationship of change in input to change in fair value measurement			Decrease	[2]
Lapse Rates [Member] | Level 3 [Member] | Maximum [Member]
Fair Value Inputs [Abstract]
Range of Values-Unobservable Inputs			75.00%	[3]
Lapse Rates [Member] | Level 3 [Member] | Minimum [Member]
Fair Value Inputs [Abstract]
Range of Values-Unobservable Inputs			0.00%	[3]
Reset Elections [Member] | Level 3 [Member]
Fair Value Inputs [Abstract]
Positive or negative relationship of change in input to change in fair value measurement			Increase	[2]
Reset Elections [Member] | Level 3 [Member] | Maximum [Member]
Fair Value Inputs [Abstract]
Range of Values-Unobservable Inputs			75.00%	[4]
Reset Elections [Member] | Level 3 [Member] | Minimum [Member]
Fair Value Inputs [Abstract]
Range of Values-Unobservable Inputs			20.00%	[4]
Equity Volatility [Member] | Level 3 [Member]
Fair Value Inputs [Abstract]
Positive or negative relationship of change in input to change in fair value measurement			Increase	[2]
Equity Volatility [Member] | Level 3 [Member] | Maximum [Member]
Fair Value Inputs [Abstract]
Range of Values-Unobservable Inputs			50.00%	[5]
Equity Volatility [Member] | Level 3 [Member] | Minimum [Member]
Fair Value Inputs [Abstract]
Range of Values-Unobservable Inputs			10.00%	[5]
Policyholder Behavior Assumptions [Member]
Fair Value Inputs [Abstract]
Derivative, Gain (Loss) on Derivative, Net	$ 0	$ 0	$ 301		$ 51

[1] Ranges represent assumed cumulative percentages of policyholders taking withdrawals and the annual amounts withdrawn.

[2] Conversely, the impact of a decrease in input would have the opposite impact to the fair value as that presented in the table.

[3] Range represents assumed annual percentages of full surrender of the underlying variable annuity contracts across all policy durations for in force business.

[4] Range represents assumed cumulative percentages of policyholders that would elect to reset their guaranteed benefit base.

[5] Range represents implied market volatilities for equity indices based on multiple pricing sources.