Note 5 - Loans and Related Allowance for Loan and Lease Losses - Troubled Debt Restructurings (Details) $ in Thousands	12 Months Ended
Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Number of contracts
Pre-modification outstanding recorded investment	$ 1,252	$ 826
Post-modification outstanding recorded investment	$ 1,252	$ 826
Commercial And Industrial [Member]
Number of contracts	3
Pre-modification outstanding recorded investment	$ 1,252
Post-modification outstanding recorded investment	$ 1,252
Commercial Real Estate Portfolio Segment [Member] \| Non-owner occupied Loan [Member]
Number of contracts		1
Pre-modification outstanding recorded investment		$ 730
Post-modification outstanding recorded investment		$ 730
Residential Portfolio Segment [Member]
Number of contracts		1
Pre-modification outstanding recorded investment		$ 96
Post-modification outstanding recorded investment		$ 96
Extended Maturity [Member]
Number of contracts
Extended Maturity [Member] \| Commercial And Industrial [Member]
Number of contracts	3
Extended Maturity [Member] \| Commercial Real Estate Portfolio Segment [Member] \| Non-owner occupied Loan [Member]
Number of contracts		1
Extended Maturity [Member] \| Residential Portfolio Segment [Member]
Number of contracts		1
Other Restructurings [Member]
Number of contracts
Other Restructurings [Member] \| Commercial And Industrial [Member]
Number of contracts	0
Other Restructurings [Member] \| Commercial Real Estate Portfolio Segment [Member] \| Non-owner occupied Loan [Member]
Number of contracts		0
Other Restructurings [Member] \| Residential Portfolio Segment [Member]
Number of contracts		0

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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI https://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524

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Amount, after troubled debt restructuring, of modified financing receivable.

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

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