Note 8 - Non-accrual Loans (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Financing Receivable Recorded Investment Past Due [Line Items]
Loans receivable	$ 23	$ 0
Loans receivable	6,731	7,921
Commercial Portfolio Segment [Member] \| Commercial and Industrial [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Loans receivable	0	0
Loans receivable	2,678	3,367
Commercial Portfolio Segment [Member] \| Construction Loans [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Loans receivable	0	0
Loans receivable	0	0
Commercial Portfolio Segment [Member] \| Secured by Commercial Real Estate [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Loans receivable	0	0
Loans receivable	1,651	1,987
Commercial Portfolio Segment [Member] \| Secured by Residential Real Estate [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Loans receivable	0	0
Loans receivable	1,198	1,458
State and Political Subdivisions Portfolio Segment [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Loans receivable	0	0
Loans receivable	0	0
Retail Portfolio Segment [Member] \| Consumer Loans [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Loans receivable	23	0
Loans receivable	81	85
Retail Portfolio Segment [Member] \| Family Residential Mortgages [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Loans receivable	0	0
Loans receivable	977	882
Retail Portfolio Segment [Member] \| Home Equity Loans and Lines [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Loans receivable	0	0
Loans receivable	$ 146	$ 142

Recorded investment in financing receivables that are 90 days or more past due and still accruing.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5111-111524

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- Definition

Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5111-111524

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- Definition

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+ References

No definition available.

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