Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended				9 Months Ended
	Sep. 30, 2021	Jun. 30, 2021	Sep. 30, 2020	Jun. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Statement of Comprehensive Income [Abstract]
Net income	$ 126.3		$ 131.7		$ 380.4	$ 244.6
Other comprehensive (loss) income:
Foreign currency translation adjustments	(6.7)		6.0		(5.1)	(11.8)
Net change in pension and post-retirement liabilities	(1.8)		(2.1)		(7.1)	(4.5)
Reclassification of pension and post-retirement benefit losses into earnings	1.8		1.4		6.0	4.4
non-cash pension settlement loss	0.3		0.3		1.1	0.3
Share of equity method investments other comprehensive income		$ 0.0		$ (1.2)	0.0	(1.2)
Net change in fair value of cash flow hedges	6.3		3.2		26.9	(3.2)
Reclassification of cash flow hedge (gains) losses into earnings	(7.8)		0.4		(21.3)	5.5
Other comprehensive (loss) income before taxes	(7.9)		8.0		0.5	(10.5)
Tax expense	(0.4)		(1.2)		(4.7)	(0.6)
Other comprehensive (loss) income, net of tax	(8.3)		6.8		(4.2)	(11.1)
Comprehensive income	$ 118.0		$ 138.5		$ 376.2	$ 233.5