Derivative Financial Instruments (Schedule of Changes in Fair Value of Derivatives) (Details) (USD $) In Millions	3 Months Ended				9 Months Ended
	Sep. 30, 2011		Sep. 30, 2010		Sep. 30, 2011		Sep. 30, 2010
Derivatives designated as cash flow hedging instruments
Gain (Loss) Recognized in Other Comprehensive Income	$ (9)		$ (17)		$ (26)		$ (40)
Gain (Loss) Recognized in Income	(9)		(24)		(57)		(21)
Derivatives not designated as hedging instruments
Gain (Loss) Recognized in Other Comprehensive Income	(9)		(17)		(26)		(40)
Gain (Loss) Recognized in Income	(9)		(24)		(57)		(21)
Tax expense recognized in Other comprehensive income (loss)	4		4		15		9
Interest Expense [Member] | Interest Rate Swap [Member] | Designated as Hedging Instrument [Member]
Derivatives designated as cash flow hedging instruments
Gain (Loss) Recognized in Income	(15)	[1]	(16)	[2]	(45)	[1]	(51)	[2]
Derivatives not designated as hedging instruments
Gain (Loss) Recognized in Income	(15)	[1]	(16)	[2]	(45)	[1]	(51)	[2]
Interest Expense [Member] | Interest Rate Swap [Member] | Not Designated as Hedging Instrument [Member]
Derivatives designated as cash flow hedging instruments
Gain (Loss) Recognized in Income	1	[3]			(2)	[3]
Derivatives not designated as hedging instruments
Gain (Loss) Recognized in Income	1	[3]			(2)	[3]
Foreign Currency Gain (Loss) [Member] | Foreign Currency Forwards and Swaps [Member] | Not Designated as Hedging Instrument [Member]
Derivatives designated as cash flow hedging instruments
Gain (Loss) Recognized in Income	5	[4]	(8)	[4]	(10)	[4]	30	[4]
Derivatives not designated as hedging instruments
Gain (Loss) Recognized in Income	5	[4]	(8)	[4]	(10)	[4]	30	[4]
Foreign Currency Forwards and Swaps [Member] | Not Designated as Hedging Instrument [Member]
Derivatives designated as cash flow hedging instruments
Gain (Loss) Recognized in Other Comprehensive Income	0		0		0		0
Derivatives not designated as hedging instruments
Gain (Loss) Recognized in Other Comprehensive Income	0		0		0		0
Equity Method Investments' Derivative [Member]
Derivatives not designated as hedging instruments
Gain (loss) associated with equity method investments' derivative	2		(1)		1		(6)
Interest Rate Swap [Member]
Derivatives not designated as hedging instruments
Tax expense recognized in Other comprehensive income (loss)	2				8		4
Interest Rate Swap [Member] | Designated as Hedging Instrument [Member]
Derivatives designated as cash flow hedging instruments
Gain (Loss) Recognized in Other Comprehensive Income	(9)	[5]	(17)	[6]	(26)	[7]	(40)	[8]
Derivatives not designated as hedging instruments
Gain (Loss) Recognized in Other Comprehensive Income	(9)	[5]	(17)	[6]	(26)	[7]	(40)	[8]
Interest Rate Swap [Member] | Not Designated as Hedging Instrument [Member]
Derivatives designated as cash flow hedging instruments
Gain (Loss) Recognized in Other Comprehensive Income	0				0
Derivatives not designated as hedging instruments
Gain (Loss) Recognized in Other Comprehensive Income	$ 0				$ 0

[1] Amount represents reclassification from Accumulated other comprehensive income (loss), net and is included in Interest expense in the unaudited interim consolidated statements of operations.

[2] Amount represents reclassification from Accumulated other comprehensive income (loss), net and is classified as Interest expense in the unaudited interim consolidated statements of operations.

[3] Included in Interest expense in the unaudited interim consolidated statements of operations.

[4] Included in Foreign exchange gain (loss), net for operating activity or Other income (expense), net for non-operating activity in the unaudited interim consolidated statements of operations.

[5] Amount excludes $2 million of gains associated with the Company’s equity method investments’ derivative activity and $2 million of tax expense recognized in Other comprehensive income (loss).

[6] Amount excludes $1 million of losses associated with the Company’s equity method investments’ derivative activity.

[7] Amount excludes $1 million of gains associated with the Company’s equity method investments’ derivative activity and $8 million of tax expense recognized in Other comprehensive income (loss).

[8] Amount excludes $6 million of losses associated with the Company's equity method investments' derivative activity and $4 million of tax expense.