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Other Debt - Additional Information (Detail) - USD ($)
3 Months Ended 12 Months Ended
Jun. 30, 2018
Dec. 31, 2020
Dec. 31, 2018
Debt Instrument [Line Items]      
Trade payable, interest bearing interest rate   12.00%  
Trade payable in accounts payable   $ 700,000  
Collateral asset carrying value   $ 0  
Proceeds from sale of marine equipment     $ 1,003,662
Magellan Offshore Services Ltd [Member] | Marine Equipment [Member]      
Debt Instrument [Line Items]      
Proceeds from sale of marine equipment $ 1,000,000    
Gain recognized from sale of marine equipment 900,000    
Contingent liability $ 500,000    
Collateral Agreement [Member]      
Debt Instrument [Line Items]      
Debt instrument maturity date   Aug. 31, 2018