Quarterly report pursuant to Section 13 or 15(d)

Financial Instruments (Summary of Derivative Instruments) (Details)

v3.8.0.1
Financial Instruments (Summary of Derivative Instruments) (Details) - Contracts designated as cash flow hedging instruments - Foreign Currency Forward Contracts - USD ($)
$ in Millions
Sep. 30, 2017
Dec. 31, 2016
Foreign Currency Forward Contracts - gains (losses)    
Derivative, notional amount $ 305 $ 138
Fair Value, Inputs, Level 2 [Member]    
Foreign Currency Forward Contracts - gains (losses)    
Contracts designated as cash flow hedging instruments $ 6 $ (2)