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Inventory - Schedule of Inventories (Detail) - USD ($)
$ in Thousands
Jun. 30, 2021
Dec. 31, 2020
Inventory [Line Items]    
Inventory, Net, Total $ 15,937 $ 19,136
Sand    
Inventory [Line Items]    
Raw material 271 428
Work in progress 7,092 10,465
Finished goods 4,497 4,400
Spare parts 4,077 3,843
Inventory, Net, Total $ 15,937 $ 19,136