Note 4 - Loans and the Allowance for Loan Losses - Loans Modified as TDRs (Details) $ in Thousands	12 Months Ended
Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Number of loans	8	19	5
Pre-modification outstanding recorded investment	$ 13,665	$ 40,310	$ 6,486
Post-modification outstanding recorded investment	$ 13,165	$ 40,310	$ 6,486
Commercial Portfolio Segment [Member]
Number of loans	2	4	1
Pre-modification outstanding recorded investment	$ 633	$ 1,276	$ 188
Post-modification outstanding recorded investment	$ 633	$ 1,276	$ 188
Commercial Real Estate Portfolio Segment [Member]
Number of loans	3	11	1
Pre-modification outstanding recorded investment	$ 12,083	$ 35,635	$ 93
Post-modification outstanding recorded investment	$ 11,583	$ 35,635	$ 93
Residential Portfolio Segment [Member]
Number of loans	3	3	2
Pre-modification outstanding recorded investment	$ 949	$ 1,758	$ 2,184
Post-modification outstanding recorded investment	$ 949	$ 1,758	$ 2,184
Commercial Construction Portfolio Segment [Member]
Number of loans		1	1
Pre-modification outstanding recorded investment		$ 1,641	$ 4,021
Post-modification outstanding recorded investment		$ 1,641	$ 4,021

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

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