Quarterly report pursuant to Section 13 or 15(d)

Investment in Derivative Instruments (Details)

v3.20.2
Investment in Derivative Instruments (Details) - USD ($)
$ in Thousands
 3 Months Ended 9 Months Ended
Jun. 30, 2020
Jun. 30, 2019
Jun. 30, 2020
Jun. 30, 2019
Sep. 30, 2019
Derivative Instruments and Hedging Activities Disclosures [Line Items]          
Realized Gain (Loss) $ (486) $ 7 $ (556) $ 12  
Unrealized Gain (Loss) 274 (212) (1,989) (543)  
Total Gain (Loss) (212) (205) (2,545) (531)  
Derivative liabilities, fair value (2,300)   (2,300)   $ (311)
Commodity swaps | Accrued Expense and Other Current Liabilities          
Derivative Instruments and Hedging Activities Disclosures [Line Items]          
Derivative liabilities, fair value (281)   (281)   0
Commodity swaps | Other Noncurrent Liabilities          
Derivative Instruments and Hedging Activities Disclosures [Line Items]          
Derivative liabilities, fair value (122)   (122)   0
Interest rate swaps | Other Noncurrent Liabilities          
Derivative Instruments and Hedging Activities Disclosures [Line Items]          
Derivative liabilities, fair value (1,897)   (1,897)   $ (311)
Cost of revenues          
Derivative Instruments and Hedging Activities Disclosures [Line Items]          
Realized Gain (Loss) (269) 0 (290) 0  
Unrealized Gain (Loss) 0 0 0 0  
Total Gain (Loss) (269) 0 (290) 0  
Other income (expense)          
Derivative Instruments and Hedging Activities Disclosures [Line Items]          
Realized Gain (Loss) 0 0 0 0  
Unrealized Gain (Loss) 394 0 (403) 0  
Total Gain (Loss) 394 0 (403) 0  
Interest expense, net          
Derivative Instruments and Hedging Activities Disclosures [Line Items]          
Realized Gain (Loss) (217) 7 (266) 12  
Unrealized Gain (Loss) (120) (212) (1,586) (543)  
Total Gain (Loss) $ (337) $ (205) $ (1,852) $ (531)