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Fair value of all derivative assets designated as fair value hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4B

-Subparagraph (c)(1)

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-Name Statement of Financial Accounting Standard (FAS)

-Number 107

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Fair value as of the balance sheet date of all derivative assets designated as foreign currency fair value hedging instruments.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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Derivative Financial Instruments - Derivatives Related to Fair Value Option Debt Financial Position (Detail) (USD $) In Millions, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Derivatives, Fair Value [Line Items]
Derivative related assets at fair value		$ 64
Derivative related liabilities at fair value	(8)	7
Debt option [Member]
Derivatives, Fair Value [Line Items]
Derivative related assets at fair value		1,501
Derivative related liabilities at fair value	(1,143)
Interest rate swaps [Member] \| Derivative Related Liabilities [Member]
Derivatives, Fair Value [Line Items]
Interest Rate Liability Derivatives Fair Value	(8)	7
Interest rate swaps [Member] \| Derivative Related Liabilities [Member] \| Debt option [Member]
Derivatives, Fair Value [Line Items]
Interest Rate Liability Derivatives Fair Value	(528)
Interest rate swaps [Member] \| Derivative financial assets [Member]
Derivatives, Fair Value [Line Items]
Interest Rate Liability Derivatives Fair Value		11
Interest rate swaps [Member] \| Derivative financial assets [Member] \| Debt option [Member]
Derivatives, Fair Value [Line Items]
Interest Rate Liability Derivatives Fair Value		693
Currency swaps [Member] \| Derivative Related Liabilities [Member]
Derivatives, Fair Value [Line Items]
Foreign Currency Liability Derivatives Fair Value
Currency swaps [Member] \| Derivative Related Liabilities [Member] \| Debt option [Member]
Derivatives, Fair Value [Line Items]
Foreign Currency Liability Derivatives Fair Value	(615)
Currency swaps [Member] \| Derivative financial assets [Member]
Derivatives, Fair Value [Line Items]
Foreign Currency Asset Derivatives Fair Value		53
Currency swaps [Member] \| Derivative financial assets [Member] \| Debt option [Member]
Derivatives, Fair Value [Line Items]
Foreign Currency Asset Derivatives Fair Value		$ 808