Note 12 - Employee Benefit Plans - Expected Future Benefit Payments (Details)	Sep. 30, 2025 USD ($)
Pension Plan [Member]
2026	$ 1,463,000
2027	1,560,000
2028	1,630,000
2029	1,701,000
2030	1,780,000
2031 - 2035	9,733,000
Other Postretirement Benefits Plan [Member]
2026	728,140
2027	753,633
2028	747,643
2029	773,121
2030	760,210
2031 - 2035	$ 3,794,802

Amount of benefit for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following current fiscal year.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-5

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

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Amount of benefit for defined benefit plan expected to be paid in next fiscal year following current fiscal year.

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