Revenue Recognition (Narrative) (Details) $ in Millions	3 Months Ended	6 Months Ended
	Jun. 30, 2018 USD ($)	Jun. 30, 2018 USD ($)
Disaggregation of Revenue [Line Items]
Standard product warranty, term	1 year
Up-front customer loyalty programs and volume commitment programs
Disaggregation of Revenue [Line Items]
Deferred revenue	$ 975.0	$ 975.0
Deferred revenue, expected recognition within remainder of year, percentage		15.00%
Deferred revenue, expected recognition during year two, percentage		25.00%
Deferred revenue, expected recognition during year three, percentage		20.00%
Deferred revenue, expected recognition thereafter, percentage		40.00%
Minimum
Disaggregation of Revenue [Line Items]
Payment term		30 days
Maximum
Disaggregation of Revenue [Line Items]
Payment term		60 days