Revenue from Contracts with Customers - Schedule of Deferred Revenue and Customer Advances by Arrangement (Parenthetical) (Detail) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Change in Contract with Customer, Liability [Line Items]
Long-term deferred revenue	$ 3.5	$ 3.3
Deferred revenue and customer advances	21.9	21.5
Deferred Revenue [Member]
Change in Contract with Customer, Liability [Line Items]
Deferred revenue and customer advances	12.4	12.4
Customer Advances [Member]
Change in Contract with Customer, Liability [Line Items]
Deferred revenue and customer advances	$ 9.5	$ 9.1