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Summary of Significant Accounting Policies - Additional Information (Detail)
 12 Months Ended
Dec. 31, 2017
USD ($)
Customer
Segment
Dec. 31, 2016
USD ($)
Dec. 31, 2015
USD ($)
Significant Accounting Policies [Line Items]      
Number of customers with supply agreement | Customer 6    
Agreements expiring period 2019    
Agreements expiring period 2020    
Railcar revenue recognized $ 7,702,000 $ 5,732,000 $ 3,543,000
Reservation revenue recognized 30,000,000 15,041,000 1,000,000
Revenue generated from transportation 48,066,000 480,000 2,294,000
Amount related to minimum commitments under customer contracts due or payable $ 0 0 0
Accounts receivables due period 30 days    
Accounts receivables, allowance for doubtful accounts   0  
Deferred revenue balance $ 0 1,615,000  
Cost of goods sold generated from shipping 50,313,000 1,172,000 2,257,000
Inventory write-down 0 0  
Debt, face amount 1,372,000 1,178,000  
Amortization of deferred financing cost 455,000 159,000 251,000
Accretion expense of debt discount 0 263,000 519,000
Tax benefit due to re-measurement of deferred tax assets and liabilities as a result of Tax Reform Act 8,500,000    
Recognized income tax interest and penalties 0    
Probable environmental matters $ 0 0  
Number of operating segment | Segment 1    
Deferred revenue recognized included in contract liability $ 1,615,000    
Remaining revenue performance obligation, percentage of revenue expected to be recognized remainder of 2018 42.00%    
Remaining revenue performance obligation, percentage of revenue expected to be recognized by 2021 58.00%    
Percentage of revenue from sand sales recognized either upon shipment or delivery 37.00%    
Percentage of revenue from reservation charges recognized when right of use expires 22.00%    
Percentage of revenue from shortfall recognized when right of use expires 1.00%    
Percentage of revenue from railcar rental recognized upon shipment 5.00%    
Percentage of revenue from transportation recognized upon shipment 35.00%    
Revolving Credit Facility      
Significant Accounting Policies [Line Items]      
Long-term Line of Credit $ 0 0  
Unbilled Revenues [Member]      
Significant Accounting Policies [Line Items]      
Deferred revenue   0  
Take-or-pay Contracts [Member]      
Significant Accounting Policies [Line Items]      
Revenue recognized for shortfall payments relating to minimum commitments 1,244,000 $ 20,902,000 $ 10,095,000
Legal costs capitalized 0    
Amortization costs incurred to obtain contract 0    
Impairment loss incurred to obtain contract $ 0