Fair Value Measurements Fair Value of Derivatives by Balance Sheet Location (Details) (USD $)	3 Months Ended					9 Months Ended
	Sep. 30, 2012	Jun. 30, 2012	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Sep. 30, 2012	Sep. 30, 2011	Dec. 31, 2011
Derivatives Fair Value [Line Items]
Goodwill and intangible asset impairment losses in period	$ 761,000,000					$ 4,492,000,000
Goodwill impairment charge	748,000,000	3,602,000,000			697,000,000	4,350,000,000	697,000,000
Goodwill	5,724,000,000					5,724,000,000		9,761,000,000
Foreign Currency Cash Flow Hedge Gain (Loss) Reclassified to Earnings, Net	3,000,000		28,000,000			29,000,000	74,000,000
Gain related to ineffective portion of hedging relationships	0		0			0	0
Unamortized losses on senior notes	3,000,000					3,000,000		4,000,000
Notional Amount of Interest Rate Derivatives	0					0		0
Unamortized gains on senior notes	66,000,000					66,000,000		73,000,000
Unrealized gain on interest rate cash flow hedges, pretax, AOCI	6,000,000					6,000,000		7,000,000
Derivative Assets	51,000,000					51,000,000		87,000,000
Derivative Liabilities	101,000,000					101,000,000		131,000,000
reduction of interest expense, related to amortization of previously terminated interest rate contracts	3,000,000					8,000,000
Impairment of Intangible Assets (Excluding Goodwill)	(13,000,000)	(129,000,000)	(9,000,000)	(12,000,000)		(142,000,000)	(21,000,000)
Designated as Hedging Instrument [Member]
Derivatives Fair Value [Line Items]
Derivative Instruments in Hedges, Assets, at Fair Value	37,000,000					37,000,000		51,000,000
Derivative Instruments in Hedges, Liabilities, at Fair Value	80,000,000					80,000,000		118,000,000
Designated as Hedging Instrument [Member] | Prepaid And Other Current Assets [Member]
Derivatives Fair Value [Line Items]
Derivative Instruments in Hedges, Assets, at Fair Value	18,000,000					18,000,000		31,000,000
Designated as Hedging Instrument [Member] | Other Long Term Assets [Member]
Derivatives Fair Value [Line Items]
Derivative Instruments in Hedges, Assets, at Fair Value	19,000,000					19,000,000		20,000,000
Designated as Hedging Instrument [Member] | Other current liabilities [Member]
Derivatives Fair Value [Line Items]
Derivative Instruments in Hedges, Liabilities, at Fair Value	55,000,000					55,000,000		69,000,000
Designated as Hedging Instrument [Member] | Other Long Term Liabilities [Member]
Derivatives Fair Value [Line Items]
Derivative Instruments in Hedges, Liabilities, at Fair Value	25,000,000					25,000,000		49,000,000
Not Designated as Hedging Instrument [Member] | Prepaid And Other Current Assets [Member]
Derivatives Fair Value [Line Items]
Derivative Instruments Not Designated as Hedging Instruments, Asset, at Fair Value	14,000,000					14,000,000		36,000,000
Not Designated as Hedging Instrument [Member] | Other current liabilities [Member]
Derivatives Fair Value [Line Items]
Derivative Instruments Not Designated as Hedging Instruments, Liability, at Fair Value	21,000,000					21,000,000		13,000,000
U.S. CRM Reporting Unit [Member]
Derivatives Fair Value [Line Items]
Allocated Goodwill	$ 216,000,000					$ 216,000,000