Fair Value Measurements (Details BS Table) (USD $) In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Derivatives Fair Value [Line Items]
Derivative Assets	$ 265	$ 121
Derivative Liabilities	63	57
Designated as Hedging Instrument [Member]
Derivatives Fair Value [Line Items]
Derivative Instruments in Hedges, Assets, at Fair Value	238	88
Derivative Instruments in Hedges, Liabilities, at Fair Value	40	30
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	27	33
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	23	27
Currency hedge contracts [Member] | Designated as Hedging Instrument [Member] | Prepaid And Other Current Assets [Member]
Derivatives Fair Value [Line Items]
Derivative Instruments in Hedges, Assets, at Fair Value	117	25
Currency hedge contracts [Member] | Designated as Hedging Instrument [Member] | Other Long Term Assets [Member]
Derivatives Fair Value [Line Items]
Derivative Instruments in Hedges, Assets, at Fair Value	120	63
Currency hedge contracts [Member] | Designated as Hedging Instrument [Member] | Other current liabilities [Member]
Derivatives Fair Value [Line Items]
Derivative Instruments in Hedges, Liabilities, at Fair Value	13	20
Currency hedge contracts [Member] | Designated as Hedging Instrument [Member] | Other Long Term Liabilities [Member]
Derivatives Fair Value [Line Items]
Derivative Instruments in Hedges, Liabilities, at Fair Value	19	10
Interest Rate Contract [Member] | Designated as Hedging Instrument [Member] | Prepaid And Other Current Assets [Member]
Derivatives Fair Value [Line Items]
Derivative Instruments in Hedges, Assets, at Fair Value	1	0
Interest Rate Contract [Member] | Designated as Hedging Instrument [Member] | Other Long Term Liabilities [Member]
Derivatives Fair Value [Line Items]
Derivative Instruments in Hedges, Liabilities, at Fair Value	$ 8	$ 0