Note 4 - Loans - Troubled Debt Restructurings (Details) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019 USD ($)	Jun. 30, 2018	Jun. 30, 2019 USD ($)	Jun. 30, 2018
Number of contracts	2	0	2	0
Pre-modification outstanding recorded investment	$ 138		$ 138
Post-modification outstanding recorded investment	$ 138		$ 138
Commercial Portfolio Segment [Member]
Number of contracts	1		1
Pre-modification outstanding recorded investment	$ 99		$ 99
Post-modification outstanding recorded investment	$ 99		$ 99
Residential Portfolio Segment [Member] \| Equity Lines [Member] \| Real Estate Loan [Member]
Number of contracts	1		1
Pre-modification outstanding recorded investment	$ 39		$ 39
Post-modification outstanding recorded investment	$ 39		$ 39

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=118936363&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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