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, 2023	Sep. 30, 2022
Beginning of year balance (in shares)	108,127	110,444
Beginning of year balance (in dollars per share)	$ 16.27	$ 15.05
Granted (in shares)	14,080	13,538
Granted (in dollars per share)	$ 21.25	$ 21.55
Vested (in shares)	0	(15,855)
Vested (in dollars per share)	$ 0	$ 12.33
End of year balance (in shares)	122,207	108,127
End of year balance (in dollars per share)	$ 16.84	$ 16.27

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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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).

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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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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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