Other Financial Statement Information - Additional Information (Detail) - USD ($) $ in Millions		3 Months Ended		12 Months Ended
	Nov. 02, 2016	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Inventory Disclosure [Abstract]
Cost of inventories for certain materials using LIFO method		$ 32.1		$ 32.0
Expense (benefit) charge to earnings from LIFO inventory changes		0.5	$ 0.2
Accrued estimate for losses		$ 2.2		$ 2.2
Name of plaintiff		Altalink, L.P.
Complaint filling date		November 2016
Estimated damages from defendants	$ 56.0