Note 5 - Loans - Impaired Loans by Loan Class (Details) - USD ($)	Mar. 31, 2017	Dec. 31, 2016
Recorded investment with no related allowance recorded	$ 11,599,000	$ 12,641,000
Unpaid principal balance with no related allowance recorded	15,435,000	16,440,000
Recorded investment with related allowance recorded	5,158,000	6,153,000
Unpaid principal balance with related allowance recorded	5,242,000	6,213,000
Related allowance	1,274,000	1,461,000
Recorded investment	16,757,000	18,794,000
Unpaid principle balance	20,677,000	22,653,000
Commercial Portfolio Segment [Member]
Recorded investment with no related allowance recorded	1,613,000	1,573,000
Unpaid principal balance with no related allowance recorded	2,511,000	2,438,000
Recorded investment with related allowance recorded	1,662,000	1,952,000
Unpaid principal balance with related allowance recorded	1,674,000	1,957,000
Related allowance	491,000	641,000
Recorded investment	3,275,000	3,525,000
Unpaid principle balance	4,185,000	4,395,000
Commercial Real Estate Portfolio Segment [Member]
Related allowance	142,000	85,000
Recorded investment	2,658,000	3,125,000
Unpaid principle balance	2,689,000	3,182,000
Commercial Real Estate Portfolio Segment [Member] \| Commercial Non-owner Occupied [Member]
Recorded investment with no related allowance recorded	1,196,000	1,196,000
Unpaid principal balance with no related allowance recorded	1,196,000	1,196,000
Recorded investment with related allowance recorded	808,000	808,000
Unpaid principal balance with related allowance recorded	808,000	808,000
Related allowance	142,000	21,000
Commercial Real Estate Portfolio Segment [Member] \| Commercial Owner Occupied Loan [Member]
Recorded investment with no related allowance recorded	654,000	784,000
Unpaid principal balance with no related allowance recorded	685,000	841,000
Recorded investment with related allowance recorded		337,000
Unpaid principal balance with related allowance recorded		337,000
Related allowance		64,000
Residential Portfolio Segment [Member]
Related allowance	628,000	721,000
Recorded investment	10,785,000	11,894,000
Unpaid principle balance	13,764,000	14,820,000
Residential Portfolio Segment [Member] \| Real Estate Loan [Member] \| Individual Tax Identification Number Loan [Member]
Recorded investment with no related allowance recorded	5,893,000	6,047,000
Unpaid principal balance with no related allowance recorded	7,560,000	7,685,000
Recorded investment with related allowance recorded	2,199,000	2,562,000
Unpaid principal balance with related allowance recorded	2,271,000	2,617,000
Related allowance	403,000	494,000
Residential Portfolio Segment [Member] \| Real Estate Loan [Member] \| Mortgage Receivable [Member]
Recorded investment with no related allowance recorded	1,337,000	1,914,000
Unpaid principal balance with no related allowance recorded	2,142,000	2,722,000
Residential Portfolio Segment [Member] \| Home Equity Loan [Member]
Recorded investment with no related allowance recorded	906,000	917,000
Unpaid principal balance with no related allowance recorded	1,341,000	1,342,000
Recorded investment with related allowance recorded	450,000	454,000
Unpaid principal balance with related allowance recorded	450,000	454,000
Related allowance	225,000	227,000
Consumer Portfolio Segment [Member]
Recorded investment with no related allowance recorded		210
Unpaid principal balance with no related allowance recorded		216
Recorded investment with related allowance recorded	39,000	40,000
Unpaid principal balance with related allowance recorded	39,000	40,000
Related allowance	13,000	14,000
Recorded investment	39,000	250,000
Unpaid principle balance	$ 39,000	$ 256,000

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=84173941&loc=SL6953550-111524

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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)(3)
-URI http://asc.fasb.org/extlink&oid=84173941&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=84173941&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=84173941&loc=d3e5212-111524

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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=84173941&loc=d3e5212-111524

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