Other Comprehensive Income (Loss) - Components of Accumulated Comprehensive Loss (Details) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021	Mar. 31, 2021	Dec. 31, 2020
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive loss	$ 701.4	$ 682.2	$ 652.9	$ 649.6
Accumulated other comprehensive loss
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive loss	(88.3)	(119.0)	$ (115.7)	$ (111.9)
Net gain (loss) on pension and OPEB liability adjustments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive loss, tax benefit	6.9	8.9
Accumulated other comprehensive loss	(15.1)	(14.4)
Unrealized gain (loss) on derivative instruments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive loss, tax benefit	2.4	2.1
Accumulated other comprehensive loss	20.8	(1.9)
Unrealized gain (loss) on foreign currency translation
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive loss, tax benefit	12.1	9.5
Accumulated other comprehensive loss	$ (94.0)	$ (102.7)