Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Consolidated Statements of Comprehensive Income [Abstract]
Net income	$ 62.7	$ 82.6	$ 51.8
Currency translation adjustments	(1.6)	0.6	(1.6)
Unrealized losses on pension benefit obligation	(0.2)	0.0	0.0
Other comprehensive income (loss), net of tax	(1.8)	0.6	(1.6)
Comprehensive income	$ 60.9	$ 83.2	$ 50.2