Debt - Summary Of Interest Expense (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Debt Instruments [Abstract]
Interest incurred	$ 155.7	$ 173.8	$ 185.0
Less: interest income	2.7	4.2	2.8
Less: interest capitalized as property, plant and equipment	2.4	1.3	2.6
Interest expense, net	$ 150.6	$ 168.3	$ 179.6