Note 5 - Non-accrual Loans (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Financing Receivable Recorded Investment Past Due [Line Items]
Loans receivable	$ 0	$ 11
Loans receivable	10,119	9,420
Commercial Portfolio Segment [Member] \| Commercial and Industrial [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Loans receivable	0	0
Loans receivable	4,798	3,433
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	3,007	3,627
Commercial Portfolio Segment [Member] \| Secured by Residential Real Estate [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Loans receivable	0	0
Loans receivable	1,866	1,803
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	93	0
Retail Portfolio Segment [Member] \| Family Residential Mortgages [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Loans receivable	0	0
Loans receivable	266	287
Retail Portfolio Segment [Member] \| Home Equity Loans and Lines [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Loans receivable	0	0
Loans receivable	$ 89	127
Finance Leases Portfolio Segment [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Loans receivable		11
Loans receivable		$ 143

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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