Note 6 - Allowance for Loan Losses and Credit Quality Information - Financial Effects of Troubled Debt Restructurings (Details) $ in Thousands	12 Months Ended
Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Number of Contracts	4	4
Pre- modification Outstanding Recorded Investment	$ 243	$ 284
Post- modification Outstanding Recorded Investment	$ 245	$ 287
Residential Portfolio Segment [Member]
Number of Contracts	0	1
Pre- modification Outstanding Recorded Investment	$ 0	$ 38
Post- modification Outstanding Recorded Investment	$ 0	$ 40
Commercial Real Estate Portfolio Segment [Member] \| Commercial Real Estate Other [Member]
Number of Contracts	1	1
Pre- modification Outstanding Recorded Investment	$ 165	$ 139
Post- modification Outstanding Recorded Investment	$ 165	$ 139
Consumer Portfolio Segment [Member]
Number of Contracts	2	1
Pre- modification Outstanding Recorded Investment	$ 47	$ 93
Post- modification Outstanding Recorded Investment	$ 49	$ 94
Commercial Portfolio Segment [Member]
Number of Contracts	1	1
Pre- modification Outstanding Recorded Investment	$ 31	$ 14
Post- modification Outstanding Recorded Investment	$ 31	$ 14

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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