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Inventory - Schedule of Inventories (Detail) - USD ($)
$ in Thousands
Jun. 30, 2020
Dec. 31, 2019
Inventory [Line Items]    
Inventory, Net, Total $ 20,287 $ 21,415
Sand    
Inventory [Line Items]    
Raw material 899 527
Work in progress 12,309 14,173
Finished goods 4,158 4,097
Spare parts 2,921 2,618
Inventory, Net, Total $ 20,287 $ 21,415