Derivative Financial Instruments (Details 12) (USD $) In Millions	Jun. 30, 2011	Dec. 31, 2010
Estimated Fair Value of Embedded Derivatives
Ceded guaranteed minimum benefits	$ 194	$ 185
Options embedded in debt or equity securities	(68)	(57)
Other	4	0
Net embedded derivatives within asset host contracts	130	128
Direct guaranteed minimum benefits	(49)	370
Assumed guaranteed minimum benefits	2,244	2,186
Other	90	78
Net embedded derivatives within liability host contracts	$ 2,285	$ 2,634

Estimated Fair Value of Embedded Derivatives Abstract.

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Estimated fair value of derivatives that are embedded in host contracts that principally include: variable annuities with guaranteed minimum withdrawal benefits, guaranteed minimum accumulation benefits, and certain guaranteed minimum income benefits.

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Estimated fair value of derivatives embedded in ceded reinsurance host contracts that reinsure the risks related to variable annuities with guaranteed minimum withdrawal benefits, guaranteed minimum accumulation benefits, and certain guaranteed minimum income benefits.

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Estimated fair value of derivatives embedded within asset host contracts that include: (a) funding agreements with equity or bond indexed crediting rates; and (b) Structured notes.

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Estimated fair value of derivatives embedded within liability host contracts that include: (a) funding agreements with equity or bond indexed crediting rates; and (b) ceded reinsurance written on a funds withheld basis within liability host contracts.

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- Definition

Estimated fair value of options embedded in debt or equity securities host contracts. The options give the issuer the right to reacquire the equity instrument for cash or other assets, or give the holder the right to convert the debt instrument into an equity instrument.

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Fair value as of the balance sheet date of the embedded derivative or group of embedded derivatives within asset host contracts.

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Fair value as of the balance sheet date of the embedded derivative or group of embedded derivatives within liability host contracts.

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