Other Comprehensive Loss - Schedule of Components of Other Comprehensive Loss and Income Tax Expense (Benefit) Allocated to Each Component (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Accumulated Other Comprehensive Income Loss [Line Items]
Other comprehensive (loss) income, Before Tax Amount	$ (5.4)	$ (34.7)
Other comprehensive (loss) income, Income Tax	1.2	(3.5)
Other comprehensive loss	(6.6)	(31.2)
Translation adjustments
Accumulated Other Comprehensive Income Loss [Line Items]
Other comprehensive (loss) income, Before Tax Amount	(10.2)	(20.0)
Other comprehensive loss	(10.2)	(20.0)
Adjustments for net periodic pension and OPEB cost
Accumulated Other Comprehensive Income Loss [Line Items]
Other comprehensive (loss) income, Before Tax Amount	1.4	1.0
Other comprehensive (loss) income, Income Tax	0.3	0.2
Other comprehensive loss	1.1	0.8
Changes in Fair Value of Derivatives
Accumulated Other Comprehensive Income Loss [Line Items]
Other comprehensive (loss) income, Before Tax Amount	3.4	(15.7)
Other comprehensive (loss) income, Income Tax	0.9	(3.7)
Other comprehensive loss	$ 2.5	$ (12.0)