Note 16 - Regulatory Assets and Liabilities - Schedule of Regulatory Assets (Details) - USD ($)	Dec. 31, 2023	Sep. 30, 2023
Regulatory assets	$ 2,868,018	$ 2,854,276
Noncurrent regulatory assets	5,350,191	5,389,445
Total regulatory assets	8,218,209	8,243,721
WNA [Member]
Regulatory assets	1,587,816	414,689
Regulatory Clause Revenues, under-Recovered [Member]
Regulatory assets	0	1,383,340
Under-recovery of RNG Revenues [Member]
Regulatory assets	1,085,177	797,804
Pension Costs [Member]
Regulatory assets	182,263	243,017
Noncurrent regulatory assets	3,786,265	3,786,265
Other Assets [Member]
Regulatory assets	12,762	15,426
Noncurrent regulatory assets	336,414	347,121
Deferred Gain (Loss) on Early Extinguishment of Debt [Member]
Noncurrent regulatory assets	1,227,512	1,256,059
Total regulatory assets	$ 1,227,512	$ 1,256,059

The amount for the individual regulatory asset as itemized in a table of regulatory assets as of the end of the period.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 980
-SubTopic 340
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481878/980-340-50-1

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