Note 7 - Long-term Debt (Details Textual) - USD ($)		3 Months Ended
Note 7 - Long-term Debt (Details Textual) - USD ($)	Sep. 05, 2025	Dec. 31, 2025	Sep. 30, 2025	Mar. 31, 2025	Apr. 03, 2023	Mar. 24, 2023	Aug. 20, 2021
Line of Credit Facility, Maximum Borrowing Capacity				$ 30,000,000		$ 20,000,000
Regulatory Asset		$ 4,543,165	$ 5,897,920
Debt Instrument, Debt Covenant Ratio of Long-term Debt to Total Capitalization, Maximum		65.00%
Debt Instrument, Debt Covenant, Ratio of Priority Debt to Total Assets, Maximum		15.00%
Debt Instrument, Debt Covenant, Interest Coverage Ratio		1.5
Debt Instrument, Variable Interest Rate, Type [Extensible Enumeration]	Secured Overnight Financing Rate (SOFR) [Member]
Deferred Gain (Loss) on Early Extinguishment of Debt [Member]
Regulatory Asset		$ 999,138	$ 1,027,684
Regulatory Asset, Amortization Period (Year)		20 years
Two Interest Rate Swaps [Member]
Derivative, Notional Amount	$ 35,600,000
Derivative, Fixed Interest Rate	5.061%
New Term Note 1 [Member]
Debt Instrument, Face Amount	$ 38,600,000
New Term Note 2 [Member]
Debt Instrument, Face Amount	$ 15,000,000
New Term Notes [Member]
Debt Instrument, Basis Spread on Variable Rate	1.55%
Debt Instrument, Origination Fee, Percentage	0.30%
Debt Instrument, Annual Fee	0.10%
MVP Southgate Note 1 [Member]
Line of Credit Facility, Maximum Borrowing Capacity	$ 1,850,000
MVP Boost Note [Member]
Line of Credit Facility, Maximum Borrowing Capacity	$ 3,650,000
MVP Southgate Notes [Member]
Debt Instrument, Basis Spread on Variable Rate	1.75%
Debt Instrument, Origination Fee, Percentage	0.25%
MVP Southgate Notes [Member] \| Interest Rate Upon Meeting Milestones [Member]
Debt Instrument, Basis Spread on Variable Rate	1.55%
Unsecured Term Notes Payable, at 30-day SOFR Average 1.20% Due August 20, 2026 [Member]
Debt Instrument, Face Amount							$ 15,000,000
Amended and Restated Delayed Term Note Entered September 24, 2021 [Member]
Debt Instrument, Face Amount					$ 10,000,000
Subsequent Letter of Commitment to Refinance [Member]
Debt Instrument, Face Amount	$ 53,600,000
One Point Eight Five Note [Member]
Debt Instrument, Face Amount	1,850,000
Three Point Six Five Note [Member]
Debt Instrument, Face Amount	$ 3,650,000

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