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Other Financial Statement Information - Additional Information (Detail) - USD ($)
$ in Millions
 3 Months Ended 6 Months Ended 12 Months Ended
Nov. 02, 2016
Jun. 30, 2021
Jun. 30, 2020
Jun. 30, 2021
Jun. 30, 2020
Dec. 31, 2020
Inventory [Line Items]            
Cost of inventories for certain materials using LIFO method   $ 32.4   $ 32.4   $ 32.0
Expense (benefit) charge to earnings from LIFO inventory changes   $ 1.3   1.8 $ 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          
Maximum [Member]            
Inventory [Line Items]            
Expense (benefit) charge to earnings from LIFO inventory changes     $ 0.1