Note 8 - Loans and Related Allowance for Loan and Lease Losses - Troubled Debt Restructurings (Details) - Commercial And Industrial [Member] $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2022 USD ($)	Jun. 30, 2022 USD ($)	Jun. 30, 2021 USD ($)
Number of contracts	1	2	2
Pre-modification outstanding recorded investment	$ 1,200	$ 1,225	$ 44
Post-modification outstanding recorded investment	$ 1,200	$ 1,225	$ 44
Extended Maturity [Member]
Number of contracts	1	2	2
Other Restructurings [Member]
Number of contracts	0	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 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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