Disputes, Litigation and Contingencies (Details) $ in Millions		12 Months Ended
	Jul. 31, 2015 patent	Dec. 31, 2010 lawsuit	Sep. 30, 2019 USD ($)	Dec. 31, 2018 USD ($)
Loss Contingencies [Line Items]
Loss Contingency, Patents Allegedly Infringed, Number | patent	7
Estimated litigation liability			$ 38	$ 29
Recorded unconditional purchase obligation				46
Other Current Liabilities [Member]
Loss Contingencies [Line Items]
Recorded unconditional purchase obligation				22
Other Noncurrent Liabilities
Loss Contingencies [Line Items]
Recorded unconditional purchase obligation			$ 24	$ 24
Neff v. Brady, et al.
Loss Contingencies [Line Items]
Number of actions filed (in lawsuits) | lawsuit		3