Note 5 - Other Investments - Schedule of Other Investments (Details) - USD ($)	3 Months Ended	9 Months Ended
Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Sep. 30, 2023
Investment in unconsolidated affiliates	$ 20,175,659		$ 20,175,659		$ 17,187,093
Equity in earnings of unconsolidated affiliate	282,604	$ 519,482	2,979,823	$ 523,581
Undistributed earnings, net of income taxes, of MVP in retained earnings, excluding impairment	11,896,616		11,896,616		9,683,797
Cash investment			8,743	2,132,679
Change in accrued capital calls			0	(803,998)
Change in investment in unconsolidated affiliates			2,988,566	$ 1,852,262
MVP [Member]
Investment in unconsolidated affiliates	20,076,299		20,076,299		17,096,476
Southgate [Member]
Investment in unconsolidated affiliates	$ 99,360		$ 99,360		$ 90,617

The amount of change in investment in unconsolidated affiliate.

No definition available.

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- Definition

The noncash increase (decrease) in unconsolidated affiliate. The noncash change reflects the affect of fluctuations in capital contributions payable during the related period.

+ References

No definition available.

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- Definition

Amount of income (loss) for proportionate share of equity method investee's income (loss).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
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- Definition

The total amount of investments that are intended to be held for an extended period of time (longer than one operating cycle).

+ References

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The cash outflow associated with the purchase of noncontrolling interest during the period.

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- Definition

Amount of consolidated retained earnings that represent undistributed (not yet received) earnings from 50 percent or less owned persons accounted for by the equity method (equity method investees).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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