Note 4 - Loans - Loans Modified as TDRs (Details) $ in Thousands	12 Months Ended
Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Number of Contracts	1	5	1
Pre-Modification Outstanding Recorded Investment	$ 1,093	$ 1,505	$ 207
Post-Modification Outstanding Recorded Investment	$ 1,093	$ 1,505	$ 207
Commercial Portfolio Segment [Member]
Number of Contracts	0	1	0
Pre-Modification Outstanding Recorded Investment	$ 0	$ 106	$ 0
Post-Modification Outstanding Recorded Investment	$ 0	$ 106	$ 0
Commercial Real Estate Portfolio Segment [Member]
Number of Contracts	1
Commercial Real Estate Portfolio Segment [Member] \| Owner Occupied Commercial Real Estate [Member]
Number of Contracts	0	0	0
Pre-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 0
Post-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 0
Commercial Real Estate Portfolio Segment [Member] \| Non-owner Occupied Commercial Real Estate [Member]
Number of Contracts	1	2	0
Pre-Modification Outstanding Recorded Investment	$ 1,093	$ 1,311	$ 0
Post-Modification Outstanding Recorded Investment	$ 1,093	$ 1,311	$ 0
Residential Portfolio Segment [Member] \| Residential [Member]
Number of Contracts	0	1	1
Pre-Modification Outstanding Recorded Investment	$ 0	$ 82	$ 207
Post-Modification Outstanding Recorded Investment	$ 0	$ 82	$ 207
Residential Portfolio Segment [Member] \| Home Equity Line of Credit [Member]
Number of Contracts	0	1	0
Pre-Modification Outstanding Recorded Investment	$ 0	$ 6	$ 0
Post-Modification Outstanding Recorded Investment	$ 0	$ 6	$ 0
Consumer Portfolio Segment [Member]
Number of Contracts	0	0	0
Pre-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 0
Post-Modification Outstanding Recorded Investment	$ 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 http://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524

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