Fair Value of Financial Instruments (Details 2) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Derivative instruments cash flow hedges:
Foreign currency buy	$ 36	$ 40
Foreign currency sell	109	86
Interest rate swaps		200
Not designated as cash flow hedges:
Foreign currency buy	12	8
Foreign currency sell	76	75
Total notional value	$ 233	$ 409

Monetary amount specified by the derivative(s). Expressed as an absolute value.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 12

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- Definition

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

+ References

No definition available.

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

+ References

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Aggregate notional amount of foreign currency derivatives to purchase a foreign currency. Notional amount refers to the number of currency units specified in the foreign currency derivative contract.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1B

-URI http://asc.fasb.org/extlink&oid=6935481&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Notional Amount

-URI http://asc.fasb.org/extlink&oid=6519104

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1A

-Subparagraph (d)

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Aggregate notional amount of foreign currency derivatives to sell a foreign currency. Notional amount refers to the number of currency units specified in the foreign currency derivative contract.

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Aggregate notional amount of all interest rate derivatives not designated as hedging instruments. Notional amount refers to the monetary amount specified in the interest rate derivative contract.

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