Guaranteed Minimum Death Benefit Contracts (Details) (USD $)	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2012	Jun. 30, 2012	Dec. 31, 2011
Guaranteed Minimum Death Benefits Reserve Table Details [Abstract]
Balance at January 1		$ 1,170,000,000	$ 1,138,000,000
Add: Unpaid Claims		40,000,000	37,000,000
Less: Reinsurance and other amounts recoverable		53,000,000	51,000,000
Balance at January 1, net		1,157,000,000	1,124,000,000
Add: Incurred benefits		13,000,000	138,000,000
Less: Paid benefits		56,000,000	105,000,000
Ending balance, net	1,114,000,000	1,114,000,000	1,157,000,000
Less: Unpaid Claims	38,000,000	38,000,000	40,000,000
Add: Reinsurance and other amounts recoverable	46,000,000	46,000,000	53,000,000
Ending balance	1,122,000,000	1,122,000,000	1,170,000,000
Guaranteed Minimum Death Benefit Reserving Assumptions [Abstract]
Lapse Rate Assumption Low	0.00%	0.00%	0.00%
Lapse Rate Assumption High	12.00%	12.00%	24.00%
Partial Surrenders Estimate Annual Election Rate Low	0.00%	0.00%	0.00%
Partial Surrenders Estimate Annual Election Rate High	13.00%	13.00%	15.00%
Volatility Assumption Varying By Equity Fund Type Low	18.00%	18.00%	16.00%
Volatility Assumption Varying By Equity Fund Type High	24.00%	24.00%	25.00%
Volatility Assumption Varying By Bond Fund Type Low	5.00%	5.00%	4.00%
Volatility Assumption Varying By Bond Fund Type High	7.00%	7.00%	10.00%
Volatility Assumption Varying By Money Market Fund Type Low	0.00%	0.00%	2.00%
Volatility Assumption Varying By Money Market Fund Type High	1.00%	1.00%	2.00%
Guaranteed Minimum Death Benefit Contracts Text Details [Abstract]
GMDB future policy benefit reserves	1,122,000,000	1,122,000,000	1,170,000,000
Guaranteed Minimum Death Benefit Mutual Fund Investment Balance		13,600,000,000	13,800,000,000
Guaranteed Minimum Death Benefit Death Benefit Coverage In Force		4,600,000,000	5,400,000,000
Guaranteed Minimum Death Benefits Total Contractholders		455,000	480,000
Guaranteed Minimum Death Benefit Reserve Strengthening Abstract [Line Items]
Pre Tax Guaranteed Minimum Death Benefit Reserve Strengthening	15,000,000	33,000,000	70,000,000
After Tax Guaranteed Minimum Death Benefit Reserve Strengthening	10,000,000	21,000,000	45,000,000
Volatility-related impacts due to equity market conditions
Guaranteed Minimum Death Benefit Reserve Strengthening Abstract [Line Items]
Pre Tax Guaranteed Minimum Death Benefit Reserve Strengthening			34,000,000
After Tax Guaranteed Minimum Death Benefit Reserve Strengthening			22,000,000
Interest rate impacts
Guaranteed Minimum Death Benefit Reserve Strengthening Abstract [Line Items]
Pre Tax Guaranteed Minimum Death Benefit Reserve Strengthening			23,000,000
After Tax Guaranteed Minimum Death Benefit Reserve Strengthening			15,000,000
Impacts of overall market declines
Guaranteed Minimum Death Benefit Reserve Strengthening Abstract [Line Items]
Pre Tax Guaranteed Minimum Death Benefit Reserve Strengthening			13,000,000
After Tax Guaranteed Minimum Death Benefit Reserve Strengthening			$ 8,000,000

After-tax expense associated with strenghtening reserves for the Guaranteed Minimum Death Benefit business.

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- Definition

Total death benefit coverage in force for the Guaranteed Minimum Death Benefit business.

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No definition available.

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Value of the underlying mutual fund investments for the Guaranteed Minimum Death Benefits business.

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No definition available.

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The known and estimated current and future amount recoverable as of the balance sheet date from reinsurers and other third parties for Guaranteed Minimum Death Benefit (GMDB) claims paid or incurred by the ceding insurer and associated GMDB claims settlement expenses, including estimated amounts for GMDB claims incurred but not reported, and future policy benefits, net of any related valuation allowance.

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Total number of underlying contractholders for the Guaranteed Minimum Death Benefit business.

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High end of the range of the anticipated rate of future terminations of contracts in force as of the balance sheet date, which is included in determining the amount of the specified guaranteed benefit obligation as of the balance sheet date.

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No definition available.

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Low end of the range of the anticipated rate of future terminations of contracts in force as of the balance sheet date, which is included in determining the amount of the specified guaranteed benefit obligation as of the balance sheet date.

+ References

No definition available.

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- Definition

The amount needed to reflect the estimated ultimate cost of settling claims relating to Guaranteed Minimum Death Benefit insured events that have occurred on or before a particular date (ordinarily, the balance sheet date) whether or not reported to the insurer at that date

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No definition available.

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Benefits paid on reinsured Guaranteed Minimum Death Benefit contracts, net of ceded reinsurance

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Total liability for future policy benefit and claim reserves for the Guaranteed Minimum Death Benefit business net of reinsurance and other amounts recoverable.

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Total liability for future policy benefit reserves for the Reinsured Guaranteed Minimum Death Benefit business.

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No definition available.

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High end of the range of the anticipated rate of partial surrenders of contracts in force as of the balance sheet date, which is included in determining the amount of the specified guaranteed benefit obligation as of the balance sheet date.

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Low end of the range of the anticipated rate of partial surrenders of contracts in force as of the balance sheet date, which is included in determining the amount of the specified guaranteed benefit obligation as of the balance sheet date.

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No definition available.

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The income statement impact of changes in Guaranteed Minimum Death Benefit reserves (benefits expense)

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No definition available.

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Pre-tax expense associated with strenghtening reserves for the Guaranteed Minimum Death Benefit business.

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No definition available.

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High end of the range of the percentage rate that is indicative of an expected degree of movement against a base line index, and which is applied against bond funds included in determining the amount of the specified guaranteed benefit obligation as of the balance sheet date.

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No definition available.

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Low end of the range of the percentage rate that is indicative of an expected degree of movement against a base line index, and which is applied against bond funds included in determining the amount of the specified guaranteed benefit obligation as of the balance sheet date.

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No definition available.

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High end of the range of the percentage rate that is indicative of an expected degree of movement against a base line index, and which is applied against equity funds included in determining the amount of the specified guaranteed benefit obligation as of the balance sheet date.

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No definition available.

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Low end of the range of the percentage rate that is indicative of an expected degree of movement against a base line index, and which is applied against equity funds included in determining the amount of the specified guaranteed benefit obligation as of the balance sheet date.

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No definition available.

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High end of the range of the percentage rate that is indicative of an expected degree of movement against a base line index, and which is applied against money market funds included in determining the amount of the specified guaranteed benefit obligation as of the balance sheet date.

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Low end of the range of the percentage rate that is indicative of an expected degree of movement against a base line index, and which is applied against money market funds included in determining the amount of the specified guaranteed benefit obligation as of the balance sheet date.

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