Investments (Details 3) (USD $) In Millions, unless otherwise specified	Jun. 30, 2011	Dec. 31, 2010
The scheduled maturities of available for sale fixed maturities
Fixed maturities amortized cost, One year or less	$ 457
Fixed maturities fair value, One year or less	471
Fixed maturities fair value, One year or less, Percent	2.00%
Fixed maturities amortized cost, After one year through five years	5,154
Fixed maturities fair value, After one year through five years	5,475
Fixed maturities fair value, After one year through five years, Percent	27.00%
Fixed maturities amortized cost, After five years through ten years	5,904
Fixed maturities fair value, After five years through ten years	6,287
Fixed maturities fair value, After five years through ten years, Percent	31.00%
Fixed maturities amortized cost, After ten years	1,984
Fixed maturities fair value, After ten years	2,054
Fixed maturities fair value, After ten years, Percent	10.00%
Fixed maturities amortized cost, Subtotal	13,499
Fixed maturities fair value, Subtotal	14,287
Fixed maturities fair value, Subtotal, Percent	70.00%
Fixed maturities amortized cost, MBS	5,918
Fixed maturities fair value, MBS	6,213
Fixed maturities fair value, MBS, Percent	30.00%
Fixed Maturity Securities [Member]
The scheduled maturities of available for sale fixed maturities
Amortized Cost	19,417	18,490
Fair Value	$ 20,500	$ 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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