Fair Value Measurements (Details) In Millions	9 Months Ended
	Sep. 30, 2011	Sep. 30, 2011 USD ($)	Dec. 31, 2010 USD ($)	Sep. 30, 2011 Total Carrying Value in the Consolidated Balance Sheet [Member] USD ($)	Dec. 31, 2010 Total Carrying Value in the Consolidated Balance Sheet [Member] USD ($)	Sep. 30, 2011 Quoted Prices in Active Markets for Identical Assets/Liabilities, Level 1 [Member] USD ($)	Dec. 31, 2010 Quoted Prices in Active Markets for Identical Assets/Liabilities, Level 1 [Member] USD ($)	Sep. 30, 2011 Significant Other Observable Inputs, Level 2 [Member] USD ($)	Dec. 31, 2010 Significant Other Observable Inputs, Level 2 [Member] USD ($)	Sep. 30, 2011 Significant Unobservable Inputs, Level 3 [Member] USD ($)	Dec. 31, 2010 Significant Unobservable Inputs, Level 3 [Member] USD ($)
Assets:
Investments				$ 47	$ 38	$ 47	$ 38	$ 0	$ 0	$ 0	$ 0
Foreign Exchange Contracts				54	26	0	0	54	25	0	1
Total Assets at Fair Value				101	64	47	38	54	25	0	1
Liabilities:
Foreign Exchange Contracts				9	17	0	0	8	17	1	0
Total Liabilities at Fair Value				9	17	0	0	8	17	1	0
Fixed Rate Debt:
Carrying amount - liability		2,871	2,691
Fair value - liability		2,891	2,791
Variable Rate Debt:
Carrying amount - liability		2,871	1,798
Fair value - liability		$ 2,719	$ 1,770
Fair Value Measurements (Textuals) [Abstract]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings, Description	Realized and unrealized gains and losses related to the embedded currency derivatives are included in Other Expense.
Fair Value, Foreign Currency Contracts, Valuation Techniques	The valuation of the embedded currency derivatives is based on an extrapolation of forward rates to the assumed expiration of the leases.