Note 11 - Other Stock Plans - Director Compensation Activity (Details) - Restricted Stock [Member] - Restricted Stock Plan for Outside Directors [Member] - $ / shares	12 Months Ended
Sep. 30, 2025	Sep. 30, 2024
Beginning of year balance (in shares)	137,764	122,207
Beginning of year balance (in dollars per share)	$ 17.11	$ 16.84
Granted (in shares)	15,898	15,557
Granted (in dollars per share)	$ 20.82	$ 19.23
End of year balance (in shares)	153,662	137,764
End of year balance (in dollars per share)	$ 17.49	$ 17.11

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(ii)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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