CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Statement of Comprehensive Income [Abstract]
Net income	$ 346.2	$ 241.7	$ 206.9
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments	40.1	4.9	(39.2)
Prior service cost arising during period, net of tax of $0	0.0	0.0	(0.3)
Net actuarial loss arising during period, net of tax of $(0.7), $(0.3), and $(0.2)	(2.5)	(1.9)	(0.7)
Settlement effects arising during period, net of tax of $0.9, $0.8, and $0	2.9	2.7	0.0
Less: amortization of actuarial (gain) loss, net of tax of $0, $0, and $0.3	(0.1)	(0.2)	1.1
Less: amortization of prior service credit, net of tax of $(0.1), $(0.1) and $(0.5).	(0.5)	(0.5)	(1.5)
Net gain (loss) on equity affiliate accumulated other comprehensive income, net of tax of $0, $0, and $(0.1)	0.2	0.0	(0.1)
Net (loss) gain on derivatives, net of tax of $(0.6), $(0.2), and $1.5	(1.1)	(0.4)	3.8
Other comprehensive income (loss), net of tax	39.0	4.6	(36.9)
Comprehensive income	$ 385.2	$ 246.3	$ 170.0