Condensed Consolidated Statements of Comprehensive Income (Loss) (Unaudited) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 18.1	$ 11.5	$ 37.3	$ 11.2
Other comprehensive income (loss), net of income tax
Unrealized income (expense) on derivatives, net of income tax provision of $0.0, $0.0, $0.0 and $0.0, respectively	(1.3)	1.3	(0.6)	(2.0)
Employee pension and postretirement benefits, net of income tax benefit of $0.0, $0.8, $0.0 and $0.8, respectively	0.4	4.2	1.4	5.6
Foreign currency translation adjustments	(13.9)	(7.1)	(15.2)	(22.5)
Total other comprehensive loss, net of income tax	(14.8)	(1.6)	(14.4)	(18.9)
Comprehensive income (loss)	$ 3.3	$ 9.9	$ 22.9	$ (7.7)