Note 8 - Loans by Loan Class Modified as TDRs (Details) $ in Thousands	3 Months Ended
Mar. 31, 2019 USD ($) contract	Mar. 31, 2018 USD ($) contract
Financing Receivable Modifications [Line Items]
Number of contracts \| contract	1
Retail Portfolio Segment [Member]
Financing Receivable Modifications [Line Items]
Number of contracts \| contract	1	1
Pre-modification outstanding recorded investment	$ 12	$ 47
Post-modification outstanding recorded investment	$ 12	$ 47
Retail Portfolio Segment [Member] \| Consumer Loans [Member]
Financing Receivable Modifications [Line Items]
Number of contracts \| contract	1
Pre-modification outstanding recorded investment	$ 12
Post-modification outstanding recorded investment	$ 12
Retail Portfolio Segment [Member] \| Home Equity Loans and Lines [Member]
Financing Receivable Modifications [Line Items]
Number of contracts \| contract		1
Pre-modification outstanding recorded investment		$ 47
Post-modification outstanding recorded investment		$ 47

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524

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Post-modification amount of investment in financing receivables modified by troubled debt restructurings.

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