Note 12 - Employee Benefit Plans - Expected Future Benefit Payments (Details)	Sep. 30, 2024 USD ($)
Pension Plan [Member]
2025	$ 1,361,000
2026	1,446,000
2027	1,554,000
2028	1,639,000
2029	1,712,000
2030 - 2034	9,483,000
Other Postretirement Benefits Plan [Member]
2025	682,000
2026	698,000
2027	730,000
2028	734,000
2029	766,000
2030 - 2034	$ 3,830,000

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 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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