Note 5 - Loans and Related Allowance for Loan and Lease Losses - Troubled Debt Restructurings (Details) $ in Thousands	12 Months Ended
Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Number of contracts
Pre-modification outstanding recorded investment	$ 826	$ 139
Post-modification outstanding recorded investment	$ 826	$ 138
Commercial And Industrial [Member]
Number of contracts		2
Pre-modification outstanding recorded investment		$ 25
Post-modification outstanding recorded investment		$ 24
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	1
Pre-modification outstanding recorded investment	$ 96	$ 114
Post-modification outstanding recorded investment	$ 96	$ 114
Extended Maturity [Member]
Number of contracts
Extended Maturity [Member] \| Commercial And Industrial [Member]
Number of contracts		2
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	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	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 http://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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