v3.7.0.1
Derivative Instruments and Hedging Activities (Narrative) (Details) - USD ($)
$ in Millions
3 Months Ended
Mar. 31, 2017
Mar. 31, 2016
Dec. 31, 2016
Designated as Hedging Instrument [Member]      
Derivative [Line Items]      
Foreign Exchange Forward Contracts Term 60 months    
Not Designated as Hedging Instrument [Member]      
Derivative [Line Items]      
Foreign Exchange Forward Contracts Term 90 days    
Gain (loss) in other income and expense $ (9) $ (13)  
Foreign Exchange Forward [Member] | Designated as Hedging Instrument [Member]      
Derivative [Line Items]      
Notional Amount of Foreign Currency Derivatives 1,733    
Foreign Exchange Forward [Member] | Not Designated as Hedging Instrument [Member]      
Derivative [Line Items]      
Fair Value, Net Asset (Liability)    
Notional Amount of Foreign Currency Derivatives 634    
Foreign Exchange Contract [Member] | Designated as Hedging Instrument [Member]      
Derivative [Line Items]      
Amount of gain (loss) to be reclassified from AOCI 54    
Interest Rate Contract [Member] | Designated as Hedging Instrument [Member]      
Derivative [Line Items]      
Amount of gain (loss) to be reclassified from AOCI $ 2