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Inventories - Additional Information (Detail) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Inventory Disclosure [Abstract]      
Amounts credited to the allowance for obsolete inventory $ 0.3 $ 0.5 $ 0.2
Items charged to the allowance for inventory write-offs $ 0.1 $ 0.3 $ 0.6