Revenue Recognition - Disaggregation of Net Sales by Place of Manufacture and to Location of Customer (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Entity Wide Information Revenue From External Customer [Line Items]
Net sales	$ 465.0	$ 421.0
Point of origin | Reportable Geographical Components | United States
Entity Wide Information Revenue From External Customer [Line Items]
Net sales	253.9	237.0
Point of origin | Reportable Geographical Components | Germany
Entity Wide Information Revenue From External Customer [Line Items]
Net sales	231.2	229.1
Point of origin | Reportable Geographical Components | Canada
Entity Wide Information Revenue From External Customer [Line Items]
Net sales	97.2	67.7
Point of origin | Reportable Geographical Components | Belgium
Entity Wide Information Revenue From External Customer [Line Items]
Net sales	66.5	66.1
Point of origin | Reportable Geographical Components | Norway
Entity Wide Information Revenue From External Customer [Line Items]
Net sales	71.0	54.3
Point of origin | Eliminations
Entity Wide Information Revenue From External Customer [Line Items]
Net sales	(254.8)	(233.2)
Point of destination | Europe
Entity Wide Information Revenue From External Customer [Line Items]
Net sales	227.3	214.5
Point of destination | North America
Entity Wide Information Revenue From External Customer [Line Items]
Net sales	145.3	132.3
Point of destination | Other
Entity Wide Information Revenue From External Customer [Line Items]
Net sales	$ 92.4	$ 74.2