CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Statement of Comprehensive Income [Abstract]
Net income before allocation to noncontrolling interests	$ 14.8	$ 91.0	$ 77.6	$ 173.5
Components of other comprehensive income (loss), net of tax
Currency translation adjustment	17.2	4.7	(28.0)	3.9
Changes in pension and postretirement plan assets and benefit obligation, net of tax	3.6	1.9	7.1	4.8
Other comprehensive income (loss), net of tax	20.8	6.6	(20.9)	8.7
Comprehensive income before allocation to noncontrolling interests	35.6	97.6	56.7	182.2
Less: Noncontrolling interests in comprehensive income	0.2	0.0	(0.1)	(0.1)
Comprehensive income attributable to common shareholders	$ 35.4	$ 97.6	$ 56.8	$ 182.3