Supplemental Information - Other (Income) Expense (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Foreign currency translation (gain)/loss	$ 1.2	$ (2.9)	$ 1.2
Royalty (income)/expense	(0.7)	(1.0)	(1.0)
Nonoperating Gains (Losses)	0.0	0.7	(1.2)
Other (income) expense, net	$ 0.5	$ (3.2)	$ (1.0)