Derivatives and Hedging Activities (Details 4) (USD $) In Millions, unless otherwise specified	Jun. 30, 2011	Dec. 31, 2010
Bifurcated Embedded Derivatives [Abstract]
Embedded Derivative, Fair Value of Embedded Derivative Asset	$ 398	$ 383
Embedded Derivative, Fair Value of Embedded Derivative Liability	322	267
Embedded Derivative, Fair Value of Embedded Derivative, Net, Total	$ 76	$ 116
Number of Contracts	1,426,903	1,223,782
Embedded Derivatives Classified In Debt [Member]
Bifurcated Embedded Derivatives [Abstract]
Number of Contracts	341	338

The number of derivative instruments of a particular group held by the entity.

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- Details

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- Definition

Fair value as of the balance sheet date of the embedded derivative or group of embedded derivatives classified as an asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 44A, 44B

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 12-16, 44A, 44B

+ Details

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- Definition

Fair value as of the balance sheet date of the embedded derivative or group of embedded derivatives classified as a liability.

+ References

+ Details

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- Definition

Net fair value as of the balance sheet date of the embedded derivative or group of embedded derivatives classified as assets, net of those classified as liabilities.

+ References

+ Details

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