Fair Value Measurements (Details in Narrative) (USD $) In Millions, unless otherwise specified	3 Months Ended					9 Months Ended
	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Sep. 30, 2012	Jun. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012
Derivative Instruments, Gain (Loss) [Line Items]
Intangible asset impairment charges	$ 0	$ 53		$ 13		$ 53	$ 142
Goodwill impairment charges	0		423	748	3,602	423	4,350
Unamortized losses on senior notes	3					3		3
Unrealized gain on interest rate cash flow hedges, pretax, AOCI	3					3		4
reduction of interest expense, related to amortization of previously terminated interest rate contracts	3					8
Notional Amount of Foreign Currency Cash Flow Hedge Derivatives	2,647					2,647		2,469
Foreign Currency Cash Flow Hedge Gain (Loss) Reclassified to Earnings, Net	15			(3)		15	(29)
Gain (Loss) in AOCI for effective portion of cash flow hedges	113					113		31
Foreign Currency Cash Flow Hedge Gain (Loss) to be Reclassified During Next 12 Months	58					58
Foreign Currency Derivative Instruments Not Designated as Hedging Instruments at Fair Value, Net	1,757					1,757		1,942
Unamortized gains on senior notes	56					56		64
Interest Rate Cash Flow Hedge Gain (Loss) to be Reclassified During Next 12 Months, Net	9					9
Time Deposits, at Carrying Value	281					281
Cash	135					135		168
Cost-method Investments, Aggregate Carrying Amount	22					22		13
Other Asset Impairment Charges	4
Asset Impairment Charges						476
Debt Instrument, Fair Value Disclosure	4,599					4,599		4,793
Fair Value, Measurements, Recurring [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Money Market Funds, at Carrying Value	155					155		39
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Money Market Funds, at Carrying Value	$ 155					$ 155		$ 39