Property, Plant, and Capitalized Software (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Property, Plant and Equipment [Line Items]
Depreciation	$ 799	$ 698	$ 613
Capitalized Computer Software, Amortization	$ 550	$ 475	$ 430