Note 14 - Commitments and Contingencies (Details Textual) BTU in Billions	1 Months Ended	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2024 USD ($) BTU $ / item	Sep. 30, 2023 USD ($)
Energy Purchase Obligation Due In Next Twelve Months (British Thermal Unit) | BTU		295
Asset Management Contract Term (Year)	2 years
Purchase Commitment Minimum Volume Required		$ 1,820,000
Franchise Agreement Term (Year)		20 years
Franchise Fee Annual Increase		3.00%
Franchise Fee Total Cost Through End of Agreement		$ 1,818,339
Natural Gas Pipeline And Storage Capacity [Member]
Cost of Goods and Services Sold		30,880,000	$ 44,253,000
Natural Gas Pipeline And Storage Capacity [Member] | Asset Management Arrangement [Member]
Cost of Goods and Services Sold		$ 1,048,000
Minimum [Member]
Purchase Commitment Purchase Price Per Energy Volume (in USD per Per Share) | $ / item		2.36
Maximum [Member]
Purchase Commitment Purchase Price Per Energy Volume (in USD per Per Share) | $ / item		3.5