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Note 7 - Loans and Related Allowance for Credit Losses - Troubled Debt Restructurings Past Due (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Sep. 30, 2024
Financing Receivable, Excluding Accrued Interest, Modified, after 12 Months	$ 7,088	$ 15,302
Financial Asset, Not Past Due [Member]
Financing Receivable, Excluding Accrued Interest, Modified, after 12 Months	7,088	15,302
Financial Asset, 30 to 59 Days Past Due [Member]
Financing Receivable, Excluding Accrued Interest, Modified, after 12 Months	0	0
Financial Asset, 60 to 89 Days Past Due [Member]
Financing Receivable, Excluding Accrued Interest, Modified, after 12 Months	0	0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Financing Receivable, Excluding Accrued Interest, Modified, after 12 Months	0	0
Financial Asset, Past Due [Member]
Financing Receivable, Excluding Accrued Interest, Modified, after 12 Months	0	0
Commercial Real Estate Portfolio Segment [Member] | Owner Occupied Loan [Member]
Financing Receivable, Excluding Accrued Interest, Modified, after 12 Months	2,224
Commercial Real Estate Portfolio Segment [Member] | Owner Occupied Loan [Member] | Financial Asset, Not Past Due [Member]
Financing Receivable, Excluding Accrued Interest, Modified, after 12 Months	2,224
Commercial Real Estate Portfolio Segment [Member] | Owner Occupied Loan [Member] | Financial Asset, 30 to 59 Days Past Due [Member]
Financing Receivable, Excluding Accrued Interest, Modified, after 12 Months	0
Commercial Real Estate Portfolio Segment [Member] | Owner Occupied Loan [Member] | Financial Asset, 60 to 89 Days Past Due [Member]
Financing Receivable, Excluding Accrued Interest, Modified, after 12 Months	0
Commercial Real Estate Portfolio Segment [Member] | Owner Occupied Loan [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Financing Receivable, Excluding Accrued Interest, Modified, after 12 Months	0
Commercial Real Estate Portfolio Segment [Member] | Owner Occupied Loan [Member] | Financial Asset, Past Due [Member]
Financing Receivable, Excluding Accrued Interest, Modified, after 12 Months	0
Commercial Real Estate Portfolio Segment [Member] | Non-owner occupied Loan [Member]
Financing Receivable, Excluding Accrued Interest, Modified, after 12 Months	1,763	13,483
Commercial Real Estate Portfolio Segment [Member] | Non-owner occupied Loan [Member] | Financial Asset, Not Past Due [Member]
Financing Receivable, Excluding Accrued Interest, Modified, after 12 Months	1,763	13,483
Commercial Real Estate Portfolio Segment [Member] | Non-owner occupied Loan [Member] | Financial Asset, 30 to 59 Days Past Due [Member]
Financing Receivable, Excluding Accrued Interest, Modified, after 12 Months	0	0
Commercial Real Estate Portfolio Segment [Member] | Non-owner occupied Loan [Member] | Financial Asset, 60 to 89 Days Past Due [Member]
Financing Receivable, Excluding Accrued Interest, Modified, after 12 Months	0	0
Commercial Real Estate Portfolio Segment [Member] | Non-owner occupied Loan [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Financing Receivable, Excluding Accrued Interest, Modified, after 12 Months	0	0
Commercial Real Estate Portfolio Segment [Member] | Non-owner occupied Loan [Member] | Financial Asset, Past Due [Member]
Financing Receivable, Excluding Accrued Interest, Modified, after 12 Months	0	0
Construction and Other [Member]
Financing Receivable, Excluding Accrued Interest, Modified, after 12 Months	2,055	1,819
Construction and Other [Member] | Financial Asset, Not Past Due [Member]
Financing Receivable, Excluding Accrued Interest, Modified, after 12 Months	2,055	1,819
Construction and Other [Member] | Financial Asset, 30 to 59 Days Past Due [Member]
Financing Receivable, Excluding Accrued Interest, Modified, after 12 Months	0	0
Construction and Other [Member] | Financial Asset, 60 to 89 Days Past Due [Member]
Financing Receivable, Excluding Accrued Interest, Modified, after 12 Months	0	0
Construction and Other [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Financing Receivable, Excluding Accrued Interest, Modified, after 12 Months	0	0
Construction and Other [Member] | Financial Asset, Past Due [Member]
Financing Receivable, Excluding Accrued Interest, Modified, after 12 Months	0	$ 0
Residential Portfolio Segment [Member]
Financing Receivable, Excluding Accrued Interest, Modified, after 12 Months	57
Residential Portfolio Segment [Member] | Financial Asset, Not Past Due [Member]
Financing Receivable, Excluding Accrued Interest, Modified, after 12 Months	57
Residential Portfolio Segment [Member] | Financial Asset, 30 to 59 Days Past Due [Member]
Financing Receivable, Excluding Accrued Interest, Modified, after 12 Months	0
Residential Portfolio Segment [Member] | Financial Asset, 60 to 89 Days Past Due [Member]
Financing Receivable, Excluding Accrued Interest, Modified, after 12 Months	0
Residential Portfolio Segment [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Financing Receivable, Excluding Accrued Interest, Modified, after 12 Months	0
Residential Portfolio Segment [Member] | Financial Asset, Past Due [Member]
Financing Receivable, Excluding Accrued Interest, Modified, after 12 Months	0
Commercial And Industrial [Member]
Financing Receivable, Excluding Accrued Interest, Modified, after 12 Months	889
Commercial And Industrial [Member] | Financial Asset, Not Past Due [Member]
Financing Receivable, Excluding Accrued Interest, Modified, after 12 Months	889
Commercial And Industrial [Member] | Financial Asset, 30 to 59 Days Past Due [Member]
Financing Receivable, Excluding Accrued Interest, Modified, after 12 Months	0
Commercial And Industrial [Member] | Financial Asset, 60 to 89 Days Past Due [Member]
Financing Receivable, Excluding Accrued Interest, Modified, after 12 Months	0
Commercial And Industrial [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Financing Receivable, Excluding Accrued Interest, Modified, after 12 Months	0
Commercial And Industrial [Member] | Financial Asset, Past Due [Member]
Financing Receivable, Excluding Accrued Interest, Modified, after 12 Months	0
Home Equity Lines of Credit [Member]
Financing Receivable, Excluding Accrued Interest, Modified, after 12 Months	100
Home Equity Lines of Credit [Member] | Financial Asset, Not Past Due [Member]
Financing Receivable, Excluding Accrued Interest, Modified, after 12 Months	100
Home Equity Lines of Credit [Member] | Financial Asset, 30 to 59 Days Past Due [Member]
Financing Receivable, Excluding Accrued Interest, Modified, after 12 Months	0
Home Equity Lines of Credit [Member] | Financial Asset, 60 to 89 Days Past Due [Member]
Financing Receivable, Excluding Accrued Interest, Modified, after 12 Months	0
Home Equity Lines of Credit [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Financing Receivable, Excluding Accrued Interest, Modified, after 12 Months	0
Home Equity Lines of Credit [Member] | Financial Asset, Past Due [Member]
Financing Receivable, Excluding Accrued Interest, Modified, after 12 Months	$ 0

X

- Definition

Amortized cost excluding accrued interest, of financing receivable 12 months after modification for debtor experiencing financial difficulty.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Subparagraph (a)(3)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-42

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