Note 4 - Allowance for Loan Losses - Segregated by Impairment Methodology (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015	Sep. 30, 2015	Dec. 31, 2014
Commercial [Member] \| Commercial and Agricultural Portfolio Segment [Member]
Ending allowance balance, individually evaluated for impairment			$ 91
Ending allowance balance, collectively evaluated for impairment	491		211
Allowance for loan losses, ending balance	491	$ 855	302	$ 497
Ending loan balance, individually evaluated for impairment	8		91
Ending loan balance, collectively evaluated for impairment	45,765		48,668
Loans	45,773	47,782	48,759
Commercial [Member] \| Real Estate Portfolio Segment [Member]
Ending allowance balance, individually evaluated for impairment	2,470		243
Ending allowance balance, collectively evaluated for impairment	2,817		3,581
Allowance for loan losses, ending balance	5,287	3,851	3,824	3,665
Ending loan balance, individually evaluated for impairment	24,363		20,049
Ending loan balance, collectively evaluated for impairment	325,029		327,654
Loans	349,392	346,262	347,703
Agricultural [Member] \| Commercial and Agricultural Portfolio Segment [Member]
Ending allowance balance, individually evaluated for impairment
Ending allowance balance, collectively evaluated for impairment	281		306
Allowance for loan losses, ending balance	281	203	306	304
Ending loan balance, individually evaluated for impairment			8
Ending loan balance, collectively evaluated for impairment	26,547		27,365
Loans	26,547	19,193	27,373
Commercial Construction [Member] \| Real Estate Portfolio Segment [Member]
Ending allowance balance, individually evaluated for impairment	22		14
Ending allowance balance, collectively evaluated for impairment	436		1,677
Allowance for loan losses, ending balance	458	691	1,691	1,223
Ending loan balance, individually evaluated for impairment	380		2,694
Ending loan balance, collectively evaluated for impairment	33,344		40,895
Loans	33,724	40,107	43,589
Residential Construction [Member] \| Real Estate Portfolio Segment [Member]
Ending allowance balance, individually evaluated for impairment
Ending allowance balance, collectively evaluated for impairment	22		138
Allowance for loan losses, ending balance	22	20	138	138
Ending loan balance, individually evaluated for impairment
Ending loan balance, collectively evaluated for impairment	10,325		10,465
Loans	10,325	9,413	10,465
Residential [Member] \| Real Estate Portfolio Segment [Member]
Ending allowance balance, individually evaluated for impairment	435		308
Ending allowance balance, collectively evaluated for impairment	1,230		1,387
Allowance for loan losses, ending balance	1,665	1,990	1,695	2,425
Ending loan balance, individually evaluated for impairment	3,200		3,380
Ending loan balance, collectively evaluated for impairment	191,845		192,420
Loans	195,045	197,002	195,800
Farmland [Member] \| Real Estate Portfolio Segment [Member]
Ending allowance balance, individually evaluated for impairment	33		57
Ending allowance balance, collectively evaluated for impairment	829		20
Allowance for loan losses, ending balance	862	912	77	104
Ending loan balance, individually evaluated for impairment	1,047		1,695
Ending loan balance, collectively evaluated for impairment	72,754		59,856
Loans	73,801	61,780	61,551
Consumer [Member] \| Consumer and Other Portfolio Segment [Member]
Ending allowance balance, individually evaluated for impairment
Ending allowance balance, collectively evaluated for impairment	103
Allowance for loan losses, ending balance	103	63		67
Ending loan balance, individually evaluated for impairment
Ending loan balance, collectively evaluated for impairment	20,378		20,958
Loans	20,378	20,605	20,958
Other [Member] \| Consumer and Other Portfolio Segment [Member]
Ending allowance balance, individually evaluated for impairment
Ending allowance balance, collectively evaluated for impairment	34		369
Allowance for loan losses, ending balance	34	19	369	379
Ending loan balance, individually evaluated for impairment
Ending loan balance, collectively evaluated for impairment	21,132		8,006
Loans	21,132	16,492	8,006
Ending allowance balance, individually evaluated for impairment	2,960		713
Ending allowance balance, collectively evaluated for impairment	6,243		7,689
Allowance for loan losses, ending balance	9,203	8,604	8,402	$ 8,802
Ending loan balance, individually evaluated for impairment	28,998		27,917
Ending loan balance, collectively evaluated for impairment	747,119		736,287
Loans	$ 776,117	$ 758,636	$ 764,204

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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The balance of financing receivables that were collectively evaluated for impairment.

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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.

+ References

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

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

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SAB Topic 6.L.1)
-URI http://asc.fasb.org/extlink&oid=27010918&loc=d3e74567-122707

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (b)(1)(ii)
-URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=65884687&loc=d3e4428-111522

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