Quarterly report pursuant to Section 13 or 15(d)

Investment in Derivative Instruments (Details)

v3.21.2
Investment in Derivative Instruments (Details) - USD ($)
$ in Thousands
3 Months Ended 9 Months Ended
Jun. 30, 2021
Jun. 30, 2020
Jun. 30, 2021
Jun. 30, 2020
Sep. 30, 2020
Derivative Instruments and Hedging Activities Disclosures [Line Items]          
Realized Gain (Loss) $ 139 $ (486) $ (254) $ (556)  
Unrealized Gain (Loss) 764 274 3,141 (1,989)  
Total Gain (Loss) 903 (212) 2,887 (2,545)  
Derivative asset, fair value 930   930    
Derivative liabilities, fair value         $ (2,211)
Prepaid expenses and other current assets          
Derivative Instruments and Hedging Activities Disclosures [Line Items]          
Derivative asset, fair value 1,203   1,203   0
Other assets          
Derivative Instruments and Hedging Activities Disclosures [Line Items]          
Derivative asset, fair value 684   684   0
Commodity swaps | Accrued Expense and Other Current Liabilities          
Derivative Instruments and Hedging Activities Disclosures [Line Items]          
Derivative liabilities, fair value 0   0   (183)
Commodity swaps | Other Noncurrent Liabilities          
Derivative Instruments and Hedging Activities Disclosures [Line Items]          
Derivative liabilities, fair value 0   0   (320)
Interest rate swaps | Other Noncurrent Liabilities          
Derivative Instruments and Hedging Activities Disclosures [Line Items]          
Derivative liabilities, fair value (957)   (957)   $ (1,708)
Cost of revenues          
Derivative Instruments and Hedging Activities Disclosures [Line Items]          
Realized Gain (Loss) 302 (269) 257 (290)  
Unrealized Gain (Loss) 632 394 2,390 (403)  
Total Gain (Loss) 934 125 2,647 (693)  
Interest expense, net          
Derivative Instruments and Hedging Activities Disclosures [Line Items]          
Realized Gain (Loss) (163) (217) (511) (266)  
Unrealized Gain (Loss) 132 (120) 751 (1,586)  
Total Gain (Loss) $ (31) $ (337) $ 240 $ (1,852)