Note 7 - Loans and Related Allowance for Credit Losses - Troubled Debt Restructurings (Details) $ in Thousands	12 Months Ended
Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Modified, Amortized cost	$ 19,622
to Total Financing Receivables, Percentage	1.33%
Commercial And Industrial [Member]
Modified, Amortized cost		$ 1,252
Number of contracts		3
Pre-modification outstanding recorded investment		$ 1,252
Commercial Portfolio Segment [Member] \| Non-owner occupied Loan [Member]
Modified, Amortized cost	$ 17,431
to Total Financing Receivables, Percentage	1.18%
Construction and Other [Member]
Modified, Amortized cost	$ 2,191
to Total Financing Receivables, Percentage	0.15%
Extended Maturity [Member]
Modified, Amortized cost	$ 17,115
Extended Maturity [Member] \| Commercial And Industrial [Member]
Number of contracts		3
Extended Maturity [Member] \| Commercial Portfolio Segment [Member] \| Non-owner occupied Loan [Member]
Modified, Amortized cost	14,924
Extended Maturity [Member] \| Construction and Other [Member]
Modified, Amortized cost	2,191
Other Restructurings [Member] \| Commercial And Industrial [Member]
Number of contracts		0
Payment Deferral [Member]
Modified, Amortized cost	0
Payment Deferral [Member] \| Commercial Portfolio Segment [Member] \| Non-owner occupied Loan [Member]
Modified, Amortized cost	0
Payment Deferral [Member] \| Construction and Other [Member]
Modified, Amortized cost	0
Payment Deferral and Extended Maturity [Member]
Modified, Amortized cost	2,507
Payment Deferral and Extended Maturity [Member] \| Commercial Portfolio Segment [Member] \| Non-owner occupied Loan [Member]
Modified, Amortized cost	2,507
Payment Deferral and Extended Maturity [Member] \| Construction and Other [Member]
Modified, Amortized cost	0
Interest Rate Reduction and Term Past Due [Member]
Modified, Amortized cost	0
Interest Rate Reduction and Term Past Due [Member] \| Commercial Portfolio Segment [Member] \| Non-owner occupied Loan [Member]
Modified, Amortized cost	0
Interest Rate Reduction and Term Past Due [Member] \| Construction and Other [Member]
Modified, Amortized cost	0
Interest Rate Reduction and Principal Forgiveness [Member]
Modified, Amortized cost	0
Interest Rate Reduction and Principal Forgiveness [Member] \| Commercial Portfolio Segment [Member] \| Non-owner occupied Loan [Member]
Modified, Amortized cost	0
Interest Rate Reduction and Principal Forgiveness [Member] \| Construction and Other [Member]
Modified, Amortized cost	$ 0

Number of financing receivables that have been modified by troubled debt restructurings.

No definition available.

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- Definition

Amount, before troubled debt restructuring, of financing receivable to be modified.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Percentage of financing receivable modified during period for debtor experiencing financial difficulty to total financing receivables.

+ References

+ Details

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- Definition

Amortized cost 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

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 12A
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481933/310-10-55-12A

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 33
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-33

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- Details

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Namespace Prefix:
Data Type:	na
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- Details

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- Details

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