Note 8 - Loans by Loan Class Modified as TDRs (Details) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019 USD ($) contract	Sep. 30, 2018 USD ($) contract	Sep. 30, 2019 USD ($) contract	Sep. 30, 2018 USD ($) contract
Financing Receivable Modifications [Line Items]
Number of contracts \| contract	1	1	1	2
Pre-modification outstanding recorded investment	$ 40	$ 38	$ 40	$ 85
Post-modification outstanding recorded investment	$ 40	$ 42	$ 40	$ 89
Commercial Portfolio Segment [Member] \| Secured by Commercial Real Estate [Member]
Financing Receivable Modifications [Line Items]
Number of contracts \| contract	1		1
Pre-modification outstanding recorded investment	$ 40		$ 40
Post-modification outstanding recorded investment	$ 40		$ 40
Retail Portfolio Segment [Member] \| Home Equity Loans and Lines [Member]
Financing Receivable Modifications [Line Items]
Number of contracts \| contract		1		2
Pre-modification outstanding recorded investment		$ 38		$ 85
Post-modification outstanding recorded investment		$ 42		$ 89

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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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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Amount, before troubled debt restructuring, of financing receivable to be modified.

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