Derivatives and Hedging (Details) (USD $) In Millions, unless otherwise specified	6 Months Ended
Jun. 30, 2011	Dec. 31, 2010
Foreign Exchange Risk Management
Foreign currency exposures, maximum hedging period (in years)	5
Net investments in foreign operations, maximum hedging period (in years)	2
Period to manage the currency exposure of global liquidity profile (in years)	1
Interest Rate Risk Management
Interest rate fluctuations, maximum hedging period (in years)	2Y
Derivatives, Notional Amount
Notional amount of interest rate cash flow hedge derivatives	$ 1,526	$ 1,326
Notional amount of foreign exchange cash flow hedge derivatives	1,548	1,522
Notional amount of cash flow hedge derivatives	3,074	2,848
Notional amount of foreign currency derivatives not eligible for hedge accounting treatment	197	238
Notional amount of derivatives	3,271	3,086
Derivatives, Fair Value
Fair value of interest rate contracts accounted for as hedges, assets	13	15
Fair value of foreign exchange contracts accounted for as hedges, assets	109	157
Total fair value of derivative assets accounted for as hedges	122	172
Fair value of foreign exchange contracts not accounted for as hedges, assets	1	2
Total fair value of derivative assets	123	174
Derivatives, Liabilities
Fair value of foreign exchange contracts accounted for as hedges, liabilities	152	157
Total fair value of derivative liabilities accounted for as hedges	152	157
Fair value of foreign exchange contracts not accounted for as hedges, liabilities	4	1
Total fair value of derivative liabilities	$ 156	$ 158

Maximum length of time over which the entity is hedging its exposure to the effects of foreign currency fluctuations on cash flows.

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Fair value as of the balance sheet date of all foreign currency derivative assets designated as hedges.

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Fair value as of the balance sheet date of all foreign currency derivative liabilities designated as hedges.

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Fair value as of the balance sheet date of all interest rate derivative assets designated as hedges.

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Maximum length of time over which the entity is hedging its exposure to the effects of foreign currency fluctuations on its net investments in foreign operations.

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Aggregate notional amount of all foreign currency derivatives designated as hedging instruments. Notional amount refers to the monetary amount specified in the derivative contract.

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Aggregate notional amount of all derivatives designated as hedging instruments

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Aggregate notional amount of all interest rate derivatives designated as hedging instruments. Notional amount refers to the monetary amount specified in the derivative contract.

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Maximum length of time over which the entity is utilizing foreign exchange derivatives that are not eligible for hedge accounting treatment.

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Fair value of a derivative asset (or nonderivative instrument) that is designated and qualifies as a hedging instrument, presented on a gross basis even when the derivative instrument is subject to master netting arrangements and qualifies for net presentation in the statement of financial position.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 205G

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 44C
-Subparagraph a
-Clause 1

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Fair value of derivative asset, presented on a gross basis even when the derivative instrument is subject to master netting arrangements and qualifies for net presentation in the statement of financial position.

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Fair value of derivative liability, presented on a gross basis even when the derivative instrument is subject to master netting arrangements and qualifies for net presentation in the statement of financial position.

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Fair value of a derivative liability (or nonderivative instrument) that is designated and qualifies as a hedging instrument, presented on a gross basis even when the derivative instrument is subject to master netting arrangements and qualifies for net presentation in the statement of financial position.

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Fair value as of the balance sheet date of all foreign currency derivative assets not designated as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 17

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Fair value as of the balance sheet date of all foreign currency derivative liabilities not designated as hedging instruments.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 17

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Maximum length of time over which the entity is hedging its exposure to the variability in future cash flows for forecasted transactions, excluding those forecasted transactions related to the payment of variable interest on existing financial instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 45
-Subparagraph b(3)

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Aggregate notional amount of all derivatives. The notional amount relates to a number of currency units, shares, bushels, pounds, or other units specified in a derivative instrument.

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Aggregate notional amount of all foreign currency derivatives not designated as hedging instruments. Notional amount refers to the number of currency units specified in the foreign currency derivative contract.

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