Note 4 - Loans and Related Allowance for Loan Losses - Major Classifications of Net Loans (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Financing Receivable Gross	$ 609,140	$ 533,710
Less allowance for loan and lease losses	(6,598)	(6,385)	$ (6,846)
Net loans	602,542	527,325
Commercial And Industrial [Member]
Financing Receivable Gross	60,630	42,536
Less allowance for loan and lease losses	(448)	(867)	(642)
Real Estate Construction Porfolio Segment [Member]
Financing Receivable Gross	23,709	22,137
Less allowance for loan and lease losses	(172)	(276)	(868)
Real Estate Mortgage Portfolio Segment [Member] \| Residential Loan [Member]
Financing Receivable Gross	270,830	232,478
Less allowance for loan and lease losses	(2,818)	(3,139)	(3,703)
Real Estate Mortgage Portfolio Segment [Member] \| Commercial Loans [Member]
Financing Receivable Gross	249,490	231,701
Less allowance for loan and lease losses	(3,135)	(2,078)	(1,576)
Consumer Portfolio Segment [Member]
Financing Receivable Gross	4,481	4,858
Less allowance for loan and lease losses	$ (25)	$ (25)	$ (57)

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953423-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(d))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-SubTopic 10
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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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