Quarterly report pursuant to Section 13 or 15(d)

Investment in Derivative Instruments (Details)

v3.21.1
Investment in Derivative Instruments (Details) - USD ($)
$ in Thousands
3 Months Ended 6 Months Ended
Mar. 31, 2021
Mar. 31, 2020
Mar. 31, 2021
Mar. 31, 2020
Sep. 30, 2020
Derivative Instruments and Hedging Activities Disclosures [Line Items]          
Realized Gain (Loss) $ (74) $ (45) $ (393) $ (70)  
Unrealized Gain (Loss) 1,213 (2,329) 2,377 (2,263)  
Total Gain (Loss) 1,139 (2,374) 1,984 (2,333)  
Derivative asset, fair value 166   166    
Derivative liabilities, fair value         $ (2,211)
Prepaid expenses and other current assets          
Derivative Instruments and Hedging Activities Disclosures [Line Items]          
Derivative asset, fair value 663   663   0
Other assets          
Derivative Instruments and Hedging Activities Disclosures [Line Items]          
Derivative asset, fair value 592   592   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 (1,089)   (1,089)   $ (1,708)
Cost of revenues          
Derivative Instruments and Hedging Activities Disclosures [Line Items]          
Realized Gain (Loss) 94 (21) (45) (21)  
Unrealized Gain (Loss) 813 (797) 1,758 (797)  
Total Gain (Loss) 907 (818) 1,713 (818)  
Interest expense, net          
Derivative Instruments and Hedging Activities Disclosures [Line Items]          
Realized Gain (Loss) (168) (24) (348) (49)  
Unrealized Gain (Loss) 400 (1,532) 619 (1,466)  
Total Gain (Loss) $ 232 $ (1,556) $ 271 $ (1,515)