CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Statement of Comprehensive Income [Abstract]
Net income before allocation to noncontrolling interests	$ 108.4	$ 62.8
Components of other comprehensive income (loss), net of tax
Currency translation adjustment	(34.9)	(45.2)
Changes in pension and postretirement plan assets and benefit obligation, net of tax	4.9	3.6
Other comprehensive loss, net of tax	(30.0)	(41.6)
Comprehensive income before allocation to noncontrolling interests	78.4	21.2
Less: Noncontrolling interests in comprehensive income	0.8	(0.3)
Comprehensive income attributable to common shareholders	$ 77.6	$ 21.5