Note 4 - Loans and Allowance for Loan Losses - Summary of Classes of Loans on Non-accrual Status (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Total nonaccrual loans	$ 1,406	$ 1,908
Commercial Portfolio Segment [Member]
Total nonaccrual loans	810	889
Commercial Real Estate Portfolio Segment [Member]
Total nonaccrual loans	342	404
Residential Portfolio Segment [Member]
Total nonaccrual loans	131	485
Consumer Portfolio Segment [Member] \| Home Equity Loan [Member]
Total nonaccrual loans	123	130
Consumer Portfolio Segment [Member] \| Other Loan [Member]
Total nonaccrual loans	$ 0	$ 0

Amount of financing receivable on nonaccrual status.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123577603&loc=d3e5111-111524

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 16
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919258-210447

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph (a)
-Subparagraph (3)

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph (a)
-Subparagraph (2)

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