Note 7 - Non-accrual Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Financing Receivable Recorded Investment Past Due [Line Items]
Loans receivable	$ 0	$ 0
Loans receivable	9,598	10,119
Commercial Portfolio Segment [Member] \| Commercial and Industrial [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Loans receivable	0	0
Loans receivable	4,670	4,798
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	2,215	3,007
Commercial Portfolio Segment [Member] \| Secured by Residential Real Estate [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Loans receivable	0	0
Loans receivable	1,812	1,866
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	0	0
Loans receivable	91	93
Retail Portfolio Segment [Member] \| Family Residential Mortgages [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Loans receivable	0	0
Loans receivable	740	266
Retail Portfolio Segment [Member] \| Home Equity Loans and Lines [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Loans receivable	0	0
Loans receivable	$ 70	$ 89

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
-Glossary Recorded Investment
-URI http://asc.fasb.org/extlink&oid=65880944

Reference 2: 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=66008989&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

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