Investments (Details 3) (USD $) In Millions, unless otherwise specified	Sep. 30, 2011	Dec. 31, 2010
The scheduled maturities of available for sale fixed maturities
Fixed maturities amortized cost, One year or less	$ 544
Fixed maturities fair value, One year or less	558
Fixed maturities fair value, One year or less, Percent	2.00%
Fixed maturities amortized cost, After one year through five years	5,076
Fixed maturities fair value, After one year through five years	5,367
Fixed maturities fair value, After one year through five years, Percent	25.00%
Fixed maturities amortized cost, After five years through ten years	6,326
Fixed maturities fair value, After five years through ten years	6,859
Fixed maturities fair value, After five years through ten years, Percent	32.00%
Fixed maturities amortized cost, After ten years	1,945
Fixed maturities fair value, After ten years	2,142
Fixed maturities fair value, After ten years, Percent	10.00%
Fixed maturities amortized cost, Subtotal	13,891
Fixed maturities fair value, Subtotal	14,926
Fixed maturities fair value, Subtotal, Percent	69.00%
Fixed maturities amortized cost, MBS	6,406
Fixed maturities fair value, MBS	6,626
Fixed maturities fair value, MBS, Percent	31.00%
Fixed Maturity Securities [Member]
The scheduled maturities of available for sale fixed maturities
Amortized Cost	20,297	18,490
Fair Value	$ 21,552	$ 19,328
Fair value, Total, Percent	100.00%

Available-for-sale Securities, Debt Maturities, after Five Through Ten Years, Fair Value, Percent.

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Available for sale securities debt maturities excluding Mbs amortized cost.

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Mortgage-backed securities, amortized cost.

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For an unclassified balance sheet, this item represents investments in debt and equity securities which are categorized neither as held-to-maturity nor trading.

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