Derivative Financial Instruments (Schedule of Changes in Fair Value of Derivatives) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2012		Mar. 31, 2011
Derivative [Line Items]
Gain (loss) recognized in Other comprehensive income	$ (1)		$ (1)
Gain (loss) recognized in Income	(13)		(28)
Tax expense recognized in Other comprehensive income (loss)	7		8
Foreign Currency Forwards and Swaps [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Gain (loss) recognized in Other comprehensive income	0		0
Equity Method Investments' Derivative [Member]
Derivative [Line Items]
Gain (loss) associated with equity method investments' derivative			1
Interest Rate Swap [Member]
Derivative [Line Items]
Tax expense recognized in Other comprehensive income (loss)	1		5
Interest Rate Swap [Member] | Designated as Hedging Instrument [Member]
Derivative [Line Items]
Gain (loss) recognized in Other comprehensive income	(1)	[1]	(1)	[2]
Interest Rate Swap [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Gain (loss) recognized in Other comprehensive income	0		0
Interest Expense [Member] | Interest Rate Swap [Member] | Designated as Hedging Instrument [Member]
Derivative [Line Items]
Gain (loss) recognized in Income	(3)	[3]	(16)	[3]
Interest Expense [Member] | Interest Rate Swap [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Gain (loss) recognized in Income	0	[4]	0	[4]
Foreign Currency Gain (Loss) [Member] | Foreign Currency Forwards and Swaps [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Gain (loss) recognized in Income	$ (10)	[5]	$ (12)	[5]

[1] Amount excludes $1 million of tax expense recognized in Other comprehensive income (loss).

[2] Amount excludes $1 million of losses associated with the Company’s equity method investments’ derivative activity and $5 million of tax expense recognized in Other comprehensive income (loss).

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

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

[5] 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.