Derivatives - Not Designated (Details) - Derivatives not designated as hedging instruments - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Derivatives not designated as hedging instruments
Gain (Loss) on Derivative Recognized in income	$ (111)	$ (132)	$ (91)	$ (91)
Foreign currency forward/option contracts | Cost of sales
Derivatives not designated as hedging instruments
Gain (Loss) on Derivative Recognized in income	3	6		5
Foreign currency forward contracts | Interest expense.
Derivatives not designated as hedging instruments
Gain (Loss) on Derivative Recognized in income	$ (114)	$ (138)	$ (91)	$ (96)