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Note 7 - Loans and Related Allowance for Credit Losses - Troubled Debt Restructurings (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Modified, Amortized cost	$ 2,224	$ 13,482	$ 5,325	$ 13,482
Total Financing Receivables, Percentage	0.10%	0.90%	0.30%	0.90%
Payment Deferral [Member]
Modified, Amortized cost	$ 2,224	$ 0	$ 2,281	$ 0
Extended Maturity [Member]
Modified, Amortized cost	0	13,482	3,044	13,482
Payment Deferral and Extended Maturity [Member]
Modified, Amortized cost	0	0	0	0
Interest Rate Reduction and Term Past Due [Member]
Modified, Amortized cost	0	0	0	0
Interest Rate Reduction and Principal Forgiveness [Member]
Modified, Amortized cost	0	0	0	0
Commercial And Industrial [Member]
Modified, Amortized cost			$ 889
Total Financing Receivables, Percentage			0.10%
Commercial And Industrial [Member] | Payment Deferral [Member]
Modified, Amortized cost			$ 0
Commercial And Industrial [Member] | Extended Maturity [Member]
Modified, Amortized cost			889
Commercial And Industrial [Member] | Payment Deferral and Extended Maturity [Member]
Modified, Amortized cost			0
Commercial And Industrial [Member] | Interest Rate Reduction and Term Past Due [Member]
Modified, Amortized cost			0
Commercial And Industrial [Member] | Interest Rate Reduction and Principal Forgiveness [Member]
Modified, Amortized cost			0
Home Equity Lines of Credit [Member]
Modified, Amortized cost			$ 100
Total Financing Receivables, Percentage			0.00%
Home Equity Lines of Credit [Member] | Payment Deferral [Member]
Modified, Amortized cost			$ 0
Home Equity Lines of Credit [Member] | Extended Maturity [Member]
Modified, Amortized cost			100
Home Equity Lines of Credit [Member] | Payment Deferral and Extended Maturity [Member]
Modified, Amortized cost			0
Home Equity Lines of Credit [Member] | Interest Rate Reduction and Term Past Due [Member]
Modified, Amortized cost			0
Home Equity Lines of Credit [Member] | Interest Rate Reduction and Principal Forgiveness [Member]
Modified, Amortized cost			0
Construction and Other [Member]
Modified, Amortized cost			$ 2,055
Total Financing Receivables, Percentage			0.10%
Construction and Other [Member] | Payment Deferral [Member]
Modified, Amortized cost			$ 0
Construction and Other [Member] | Extended Maturity [Member]
Modified, Amortized cost			2,055
Construction and Other [Member] | Payment Deferral and Extended Maturity [Member]
Modified, Amortized cost			0
Construction and Other [Member] | Interest Rate Reduction and Term Past Due [Member]
Modified, Amortized cost			0
Construction and Other [Member] | Interest Rate Reduction and Principal Forgiveness [Member]
Modified, Amortized cost			0
Commercial Real Estate Portfolio Segment [Member] | Owner Occupied Loan [Member]
Modified, Amortized cost	$ 2,224		$ 2,224
Total Financing Receivables, Percentage	0.10%		0.10%
Commercial Real Estate Portfolio Segment [Member] | Owner Occupied Loan [Member] | Payment Deferral [Member]
Modified, Amortized cost	$ 2,224		$ 2,224
Commercial Real Estate Portfolio Segment [Member] | Owner Occupied Loan [Member] | Extended Maturity [Member]
Modified, Amortized cost	0		0
Commercial Real Estate Portfolio Segment [Member] | Owner Occupied Loan [Member] | Payment Deferral and Extended Maturity [Member]
Modified, Amortized cost	0		0
Commercial Real Estate Portfolio Segment [Member] | Owner Occupied Loan [Member] | Interest Rate Reduction and Term Past Due [Member]
Modified, Amortized cost	0		0
Commercial Real Estate Portfolio Segment [Member] | Owner Occupied Loan [Member] | Interest Rate Reduction and Principal Forgiveness [Member]
Modified, Amortized cost	$ 0		0
Commercial Real Estate Portfolio Segment [Member] | Non-owner occupied Loan [Member]
Modified, Amortized cost		$ 13,482		$ 13,482
Total Financing Receivables, Percentage		0.90%		0.90%
Commercial Real Estate Portfolio Segment [Member] | Non-owner occupied Loan [Member] | Payment Deferral [Member]
Modified, Amortized cost		$ 0		$ 0
Commercial Real Estate Portfolio Segment [Member] | Non-owner occupied Loan [Member] | Extended Maturity [Member]
Modified, Amortized cost		13,482		13,482
Commercial Real Estate Portfolio Segment [Member] | Non-owner occupied Loan [Member] | Payment Deferral and Extended Maturity [Member]
Modified, Amortized cost		0		0
Commercial Real Estate Portfolio Segment [Member] | Non-owner occupied Loan [Member] | Interest Rate Reduction and Term Past Due [Member]
Modified, Amortized cost		0		0
Commercial Real Estate Portfolio Segment [Member] | Non-owner occupied Loan [Member] | Interest Rate Reduction and Principal Forgiveness [Member]
Modified, Amortized cost		$ 0		$ 0
Residential Portfolio Segment [Member]
Modified, Amortized cost			$ 57
Total Financing Receivables, Percentage			0.00%
Residential Portfolio Segment [Member] | Payment Deferral [Member]
Modified, Amortized cost			$ 57
Residential Portfolio Segment [Member] | Extended Maturity [Member]
Modified, Amortized cost			0
Residential Portfolio Segment [Member] | Payment Deferral and Extended Maturity [Member]
Modified, Amortized cost			0
Residential Portfolio Segment [Member] | Interest Rate Reduction and Term Past Due [Member]
Modified, Amortized cost			0
Residential Portfolio Segment [Member] | Interest Rate Reduction and Principal Forgiveness [Member]
Modified, Amortized cost			$ 0

X

- Definition

Amortized cost excluding accrued interest, of financing receivable modified during period 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)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-42

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- Definition

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+ References

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

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