Quarterly report pursuant to Section 13 or 15(d)

BASIS OF PRESENTATION, CONSOLIDATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Narrative (Details)

v3.20.2
BASIS OF PRESENTATION, CONSOLIDATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Narrative (Details)
3 Months Ended
Oct. 31, 2019
USD ($)
flight_hour
Oct. 30, 2019
USD ($)
Jun. 30, 2019
USD ($)
Jun. 30, 2020
USD ($)
Mar. 31, 2020
USD ($)
Mar. 31, 2019
USD ($)
contract
Dec. 07, 2012
Item Affected [Line Items]              
Restricted cash       $ 3,493,000 $ 2,459,000    
Allowance for doubtful accounts receivable       400,000 400,000    
Pre-operating costs $ 0 $ 8,800,000       $ 9,800,000  
Number of client contracts | contract           2  
Amortization of other deferred charges     $ 2,400,000        
Useful lives, hour restriction | flight_hour 30,000            
Minimum              
Item Affected [Line Items]              
Useful lives   P5Y          
Salvage value 5.00% 30.00%          
Maximum              
Item Affected [Line Items]              
Useful lives P30Y P15Y          
Salvage value 25.00% 50.00%          
Affiliated Entity              
Item Affected [Line Items]              
Allowance for doubtful accounts receivable       0 $ 0    
Post-emergence bankruptcy related payments              
Item Affected [Line Items]              
Restricted cash       800,000      
Norway payroll withholding taxes              
Item Affected [Line Items]              
Restricted cash       $ 2,700,000      
Senior Notes | 7.750% Senior Notes              
Item Affected [Line Items]              
Stated interest rate       7.75%     7.75%