Derivative Financial Instruments (Details Textual) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2012	Mar. 31, 2011	Dec. 31, 2011
Derivatives, Fair Value [Line Items]
Derivative Assets	$ 78		$ 26
Derivative Liabilities	33		96
Derivative Financial Instruments (Textual) [Abstract]
Minimum Derivative Financial Instrument's Term (Months)	2 months
Maximum Derivative Financial Instrument's Term (Months)	24 months
Fair Value of Foreign Currency Forward Contracts	45
Amount of interest rate swap	0
Accumulated other comprehensive income (loss), reclassified	(6)
Amount of gain (loss) recognized in income on derivative (ineffective portion)	(1)	(3)
Amount of gain (loss) recognized in income on derivative (amount excluded from hedge effectiveness)	(1)	(4)
Fair Value, Inputs, Level 2 [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets	78
Derivative Liabilities	$ 33

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Maximum derivative financial instrument's term.

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- Definition

Minimum derivative financial instrument's term.

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No definition available.

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- Definition

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.

+ 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 (a),(c)

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 44C

-Subparagraph a

-Clause 1

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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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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The portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments representing (a) the amount of the hedge ineffectiveness and (b) the amount, if any, excluded from the assessment of hedge effectiveness.

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

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-Number 133

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Fair value as of the balance sheet date of foreign currency derivative assets, net of foreign currency derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized on the balance sheet.

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Net gain (loss) recognized in earnings during the reporting period representing the amount of the fair value of the hedges' ineffectiveness.

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Fair value as of the balance sheet date of interest rate derivative assets, net of interest rate derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized on the balance sheet.

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-Number 107

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Net of tax effect of the reclassification adjustment for accumulated gains and losses from derivative instrument designated and qualifying as the effective portion of cash flow hedges included in accumulated comprehensive income that was realized in net income during the period.

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-Glossary Reclassification Adjustments

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