Fair Value Measurements (Details) (USD $) In Millions	Sep. 30, 2011	Dec. 31, 2010
Level 1 [Member]
Assets
Cash equivalents	$ 193	$ 347
Derivatives (foreign currency forward contracts)	0	0
Total Assets	193	347
Level 1 [Member]
Liabilities
Derivatives (foreign currency forward contracts)	0	0
Level 2 [Member]
Assets
Cash equivalents	0	0
Derivatives (foreign currency forward contracts)	11	22
Total Assets	11	22
Level 2 [Member]
Liabilities
Derivatives (foreign currency forward contracts)	11	5
Level 3 [Member]
Assets
Cash equivalents	0	0
Derivatives (foreign currency forward contracts)	0	0
Total Assets	0	0
Level 3 [Member]
Liabilities
Derivatives (foreign currency forward contracts)	$ 0	$ 0

Fair Value, Assets Measured On Recurring Basis, Total Assets.

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This element represents a certain statement of financial position asset caption which represents a class of assets, or which may include an individual asset, measured at fair value on a recurring basis.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 157

-Paragraph 32

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