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Property, Plant and Equipment - Additional Information (Detail) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Property, Plant and Equipment [Line Items]      
Property, Plant and Equipment, Gross $ 573,031 $ 393,812  
Depreciation expense 17,500 13,600 $ 13,400
Construction in Process [Member]      
Property, Plant and Equipment [Line Items]      
Property, Plant and Equipment, Gross $ 157,465 $ 59,257