Goodwill and Other Intangible Assets - Schedule of Other Intangible Rollforward (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Finite-lived Intangible Assets [Roll Forward]
Other intangible assets, beginning balance	$ 10,269	$ 10,420
Acquisitions	548	274
Divestitures		(216)
Foreign currency translation	(45)	69
Other activity, net	(21)	(6)
Other intangible assets, ending balance	$ 10,462	$ 10,269