Note 5 - Loans by Loan Class Modified as TDRs (Details) $ in Thousands	12 Months Ended
Dec. 31, 2019 USD ($) contract	Dec. 31, 2018 USD ($) contract
Financing Receivable Modifications [Line Items]
Number of contracts \| contract	7	4
Pre- modification outstanding recorded investment	$ 3,181	$ 233
Post- modification outstanding recorded investment	$ 3,188	$ 214
Commercial Portfolio Segment [Member]
Financing Receivable Modifications [Line Items]
Number of contracts \| contract	3
Commercial Portfolio Segment [Member] \| Commercial and Industrial [Member]
Financing Receivable Modifications [Line Items]
Number of contracts \| contract	1
Pre- modification outstanding recorded investment	$ 641
Post- modification outstanding recorded investment	$ 126
Commercial Portfolio Segment [Member] \| Secured by Commercial Real Estate [Member]
Financing Receivable Modifications [Line Items]
Number of contracts \| contract	3	1
Pre- modification outstanding recorded investment	$ 2,540	$ 99
Post- modification outstanding recorded investment	$ 2,528	$ 99
Commercial Portfolio Segment [Member] \| Secured by Residential Real Estate [Member]
Financing Receivable Modifications [Line Items]
Number of contracts \| contract	3	1
Pre- modification outstanding recorded investment		$ 39
Post- modification outstanding recorded investment	$ 534	$ 29
Retail Portfolio Segment [Member] \| Home Equity Loans and Lines [Member]
Financing Receivable Modifications [Line Items]
Number of contracts \| contract		2
Pre- modification outstanding recorded investment		$ 95
Post- modification outstanding recorded investment		$ 86

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Number of financing receivables that have been modified by troubled debt restructurings.

+ References

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=118936363&loc=SL6953676-111524

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Amount, after troubled debt restructuring, of modified financing receivable.

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