Invested Assets (Details 2) (USD $) In Millions	Jun. 30, 2011	Dec. 31, 2010
Components of unrealized appreciation or depreciation of investments [Abstract]
Fixed maturities, Gross unrealized appreciation	$ 1,814	$ 1,630
Fixed maturities, Gross unrealized depreciation	103	172
Fixed maturities, Unrealized appreciation (depreciation), Net	1,711	1,458
Equity securities, Gross unrealized appreciation	421	340
Equity securities, Gross unrealized depreciation	50	75
Equity securities, Unrealized appreciation (depreciation), Net	371	265
Total fixed maturities and equity securities, Unrealized appreciation (depreciation), Net	2,082	1,723
Deferred income tax liability	729	603
Total fixed maturities and equity securities, Unrealized appreciation (depreciation), Net of tax	$ 1,353	$ 1,120

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The amount for all deferred tax assets and liabilities relating to unrealized appreciation or depreciation as of the balance sheet date.

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The excess of the fair value of equity securities over its amortized cost which excess value has not been recognized in earnings of the entity.

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The excess of amortized cost of equity securities over its fair value which deficiency has not been recognized in earnings of the entity.

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The net excess or deficiency of the fair value of equity securities over or under its amortized cost which has not been recognized in earnings of the entity.

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The net excess or deficiency of the fair value of available for sale securities over or under its amortized cost which has not been recognized in earnings of the entity.

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The net excess or deficiency of the fair value of fixed maturities and equity securities over or under its amortized cost which has not been recognized in earnings of the entity net of deferred income tax.

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The excess of the fair value of fixed maturities over its amortized cost which excess value has not been recognized in earnings of the entity.

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The excess of amortized cost of fixed maturities over its fair value which deficiency has not been recognized in earnings of the entity.

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The net excess or deficiency of the fair value of fixed maturities over or under its amortized cost which has not been recognized in earnings of the entity.

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