Note 5 - Loans - Impaired Loans by Loan Class (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Commercial Portfolio Segment [Member]
Recorded investment with no related allowance recorded	$ 1,710	$ 1,282
Unpaid principal balance with no related allowance recorded	2,467	1,519
Recorded investment with related allowance recorded	1,199	761
Unpaid principal balance with related allowance recorded	1,834	820
Related allowance	91	122
Impaired Financing Receivable, Recorded Investment	2,909	2,043
Unpaid principle balance	4,301	2,339
Commercial Real Estate Portfolio Segment [Member] \| Commercial Non-owner Occupied [Member]
Recorded investment with no related allowance recorded	1,197	5,488
Unpaid principal balance with no related allowance recorded	1,197	6,226
Recorded investment with related allowance recorded	816	824
Unpaid principal balance with related allowance recorded	816	824
Related allowance	29	35
Commercial Real Estate Portfolio Segment [Member] \| Commercial Owner Occupied Loan [Member]
Recorded investment with no related allowance recorded	816	1,071
Unpaid principal balance with no related allowance recorded	853	1,794
Recorded investment with related allowance recorded	344	350
Unpaid principal balance with related allowance recorded	344	350
Related allowance	63	62
Commercial Real Estate Portfolio Segment [Member]
Related allowance	92	97
Impaired Financing Receivable, Recorded Investment	3,173	7,733
Unpaid principle balance	3,210	9,194
Residential Portfolio Segment [Member] \| Real Estate Loan [Member] \| Individual Tax Identification Number Loan [Member]
Recorded investment with no related allowance recorded	6,703	7,063
Unpaid principal balance with no related allowance recorded	8,377	8,662
Recorded investment with related allowance recorded	2,360	2,044
Unpaid principal balance with related allowance recorded	2,365	2,089
Related allowance	434	321
Residential Portfolio Segment [Member] \| Real Estate Loan [Member] \| Mortgage Receivable [Member]
Recorded investment with no related allowance recorded	1,824	1,775
Unpaid principal balance with no related allowance recorded	2,591	2,775
Residential Portfolio Segment [Member] \| Home Equity Loan [Member]
Recorded investment with no related allowance recorded	1,138	142
Unpaid principal balance with no related allowance recorded	1,454	142
Recorded investment with related allowance recorded	548	558
Unpaid principal balance with related allowance recorded	548	558
Related allowance	274	279
Residential Portfolio Segment [Member]
Related allowance	708	600
Impaired Financing Receivable, Recorded Investment	12,573	11,582
Unpaid principle balance	15,335	14,226
Consumer Portfolio Segment [Member]
Recorded investment with no related allowance recorded	235
Unpaid principal balance with no related allowance recorded	235
Recorded investment with related allowance recorded	31	32
Unpaid principal balance with related allowance recorded	31	32
Related allowance	12	13
Impaired Financing Receivable, Recorded Investment	266	32
Unpaid principle balance	266	32
Recorded investment with no related allowance recorded	13,623	16,821
Unpaid principal balance with no related allowance recorded	17,174	21,118
Recorded investment with related allowance recorded	5,298	4,569
Unpaid principal balance with related allowance recorded	5,938	4,673
Related allowance	903	832
Impaired Financing Receivable, Recorded Investment	18,921	21,390
Unpaid principle balance	$ 23,112	$ 25,791

Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953550-111524

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- Definition

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+ References

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 15
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (a)(4)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524

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