Other Comprehensive Loss - Changes in Components of Other Comprehensive Income (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Accumulated Other Comprehensive Income (Loss) [Line Items]
Pre-tax	$ (19.0)	$ (2.7)
Tax	3.3	3.4
Other comprehensive (loss) income	(15.7)	0.7
Net gain (loss) on pension and OPEB liability adjustments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Pre-tax	0.7	(0.6)
Tax	(0.2)	1.1
Other comprehensive (loss) income	0.5	0.5
Unrealized (loss) gain on derivative instruments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Pre-tax	(15.6)	(0.5)
Tax	2.9	0.0
Other comprehensive (loss) income	(12.7)	(0.5)
Unrealized (loss) gain on foreign currency translation
Accumulated Other Comprehensive Income (Loss) [Line Items]
Pre-tax	(4.1)	(1.6)
Tax	0.6	2.3
Other comprehensive (loss) income	$ (3.5)	$ 0.7