Accumulated Other Comprehensive Loss - Components of Accumulated Other Comprehensive Income (Details) - USD ($) $ in Millions	3 Months Ended						9 Months Ended
	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2021	Sep. 30, 2020
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	$ 2,032.6	$ 1,829.0	$ 1,854.5	$ 1,606.3	$ 1,490.2	$ 1,573.2	$ 1,854.5	$ 1,573.2
Other comprehensive income (loss) before reclassifications							(48.8)
Amounts reclassified out from accumulated other comprehensive income (loss)							3.7
Other comprehensive (loss) income, net of tax	(22.5)	7.0	(29.6)	28.3	4.5	(42.7)	(45.1)	(9.9)
Ending balance	2,202.3	2,032.6	1,829.0	1,718.9	1,606.3	1,490.2	2,202.3	1,718.9
(Losses) gains on derivatives
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance			(1.9)				(1.9)
Other comprehensive income (loss) before reclassifications							(2.5)
Amounts reclassified out from accumulated other comprehensive income (loss)							3.2
Other comprehensive (loss) income, net of tax							0.7
Ending balance	(1.2)						(1.2)
Change in equity affiliate investment AOCI
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance			0.6				0.6
Other comprehensive income (loss) before reclassifications							0.0
Amounts reclassified out from accumulated other comprehensive income (loss)							0.0
Other comprehensive (loss) income, net of tax							0.0
Ending balance	0.6						0.6
Defined benefit pension and other postretirement plans
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance			(40.5)				(40.5)
Other comprehensive income (loss) before reclassifications							0.6
Amounts reclassified out from accumulated other comprehensive income (loss)							0.5
Other comprehensive (loss) income, net of tax							1.1
Ending balance	(39.4)						(39.4)
Foreign currency translation
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance			(68.8)				(68.8)
Other comprehensive income (loss) before reclassifications							(46.9)
Amounts reclassified out from accumulated other comprehensive income (loss)							0.0
Other comprehensive (loss) income, net of tax							(46.9)
Ending balance	(115.7)						(115.7)
Accumulated other comprehensive loss
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(133.2)	(140.2)	(110.6)	(187.8)	(192.3)	(149.6)	(110.6)	(149.6)
Other comprehensive (loss) income, net of tax	(22.5)	7.0	(29.6)	28.3	4.5	(42.7)
Ending balance	$ (155.7)	$ (133.2)	$ (140.2)	$ (159.5)	$ (187.8)	$ (192.3)	$ (155.7)	$ (159.5)