Note 7 - Loans - Impaired Loans (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Unpaid principal - with no allowance	$ 6,012	$ 9,856
Recorded investment - with no allowance	5,388	7,488
Unpaid principal - with allowance	3,581	3,372
Recorded investment - with allowance	3,581	3,372
Related allowance	1,167	674
Unpaid principal	9,593	13,228
Recorded investment	8,969	10,860
Residential Portfolio Segment [Member] \| Real Estate Loan [Member] \| Senior Lien [Member]
Unpaid principal - with no allowance	752	783
Recorded investment - with no allowance	723	753
Residential Portfolio Segment [Member] \| Real Estate Loan [Member] \| Junior Lien [Member]
Unpaid principal - with no allowance	62	68
Recorded investment - with no allowance	62	68
Commercial Portfolio Segment [Member] \| Real Estate Loan [Member]
Unpaid principal - with no allowance	3,231	6,975
Recorded investment - with no allowance	3,231	5,232
Unpaid principal - with allowance	2,686	2,773
Recorded investment - with allowance	2,686	2,773
Related allowance	952	528
Commercial Portfolio Segment [Member] \| Commercial and Industrial [Member]
Unpaid principal - with no allowance	78	117
Recorded investment - with no allowance	78	117
Unpaid principal - with allowance	398	95
Recorded investment - with allowance	398	95
Related allowance	165	95
Commercial Portfolio Segment [Member] \| Loans Secured by Farmland [Member]
Unpaid principal - with no allowance	874	890
Recorded investment - with no allowance	874	890
Unpaid principal - with allowance	497	504
Recorded investment - with allowance	497	504
Related allowance	50	51
Commercial Portfolio Segment [Member] \| Multifamily 5 or More Residential [Member]
Unpaid principal - with no allowance	987	987
Recorded investment - with no allowance	392	392
Commercial Portfolio Segment [Member] \| Agricultural Loans [Member]
Unpaid principal - with no allowance	8	13
Recorded investment - with no allowance	8	13
Consumer Portfolio Segment [Member]
Unpaid principal - with no allowance	20	23
Recorded investment - with no allowance	$ 20	$ 23

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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- Definition

Amount of allowance for credit losses related to recorded investment.

+ 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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+ 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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