Regulatory Assets and Liabilities (Schedule of Regulatory Liabilities) (Details) - USD ($)	Jun. 30, 2020	Sep. 30, 2019
Regulatory Liabilities [Line Items]
Current regulatory liabilities	$ 817,437	$ 4,877,603
Deferred Credits and Other Liabilities:
Asset retirement obligations	7,038,745	6,788,683
Regulatory cost of retirement obligations	12,563,824	11,892,352
Noncurrent regulatory liabilities - excess deferred income taxes	10,748,044	10,934,434
Total non-current	30,350,613	29,615,469
Total regulatory liabilities	31,168,050	34,493,072
Over-recovery of gas costs [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities	264,383	161,837
Over-recovery of SAVE Plan revenues [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities	197,195	574,181
Rate refund [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities	0	3,827,588
Excess deferred income taxes [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities	205,353	205,353
Other deferred liabilities [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities	$ 150,506	$ 108,644