Note 4 - Allowance for Loan Losses Segregated by Impairment Methodology (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015	Jun. 30, 2015	Dec. 31, 2014
Commercial [Member] \| Commercial and Agricultural Portfolio Segment [Member]
Ending allowance balance, individually evaluated for impairment			$ 92
Ending allowance balance, collectively evaluated for impairment	555		254
Loans and Leases Receivable, Allowance	555	$ 855	346	$ 497
Ending loan balance, individually evaluated for impairment	9		91
Ending loan balance, collectively evaluated for impairment	47,925		52,415
Ending loan balance, total	47,934	47,782	52,506
Commercial [Member] \| Real Estate Portfolio Segment [Member]
Ending allowance balance, individually evaluated for impairment	2,886		278
Ending allowance balance, collectively evaluated for impairment	2,712		3,544
Loans and Leases Receivable, Allowance	5,598	3,851	3,822	3,665
Ending loan balance, individually evaluated for impairment	17,463		20,537
Ending loan balance, collectively evaluated for impairment	327,718		320,630
Ending loan balance, total	345,181	346,262	341,167
Agricultural [Member] \| Commercial and Agricultural Portfolio Segment [Member]
Ending allowance balance, individually evaluated for impairment
Ending allowance balance, collectively evaluated for impairment	251		309
Loans and Leases Receivable, Allowance	251	203	309	304
Ending loan balance, individually evaluated for impairment			8
Ending loan balance, collectively evaluated for impairment	24,307		24,011
Ending loan balance, total	24,307	19,193	24,019
Commercial Construction [Member] \| Real Estate Portfolio Segment [Member]
Ending allowance balance, individually evaluated for impairment	22		18
Ending allowance balance, collectively evaluated for impairment	416		1,568
Loans and Leases Receivable, Allowance	438	691	1,586	1,223
Ending loan balance, individually evaluated for impairment	384		3,313
Ending loan balance, collectively evaluated for impairment	31,908		43,386
Ending loan balance, total	32,292	40,107	46,699
Residential Construction [Member] \| Real Estate Portfolio Segment [Member]
Ending allowance balance, individually evaluated for impairment
Ending allowance balance, collectively evaluated for impairment	18		138
Loans and Leases Receivable, Allowance	18	20	138	138
Ending loan balance, individually evaluated for impairment
Ending loan balance, collectively evaluated for impairment	9,141		11,327
Ending loan balance, total	9,141	9,413	11,327
Residential [Member] \| Real Estate Portfolio Segment [Member]
Ending allowance balance, individually evaluated for impairment	440		320
Ending allowance balance, collectively evaluated for impairment	1,172		1,453
Loans and Leases Receivable, Allowance	1,612	1,990	1,773	2,425
Ending loan balance, individually evaluated for impairment	3,609		3,432
Ending loan balance, collectively evaluated for impairment	192,531		199,373
Ending loan balance, total	196,140	197,002	202,805
Farmland [Member] \| Real Estate Portfolio Segment [Member]
Ending allowance balance, individually evaluated for impairment	33		59
Ending allowance balance, collectively evaluated for impairment	763		47
Loans and Leases Receivable, Allowance	796	912	106	104
Ending loan balance, individually evaluated for impairment	1,048		1,697
Ending loan balance, collectively evaluated for impairment	69,089		52,438
Ending loan balance, total	70,137	61,780	54,135
Consumer [Member] \| Consumer and Other Portfolio Segment [Member]
Ending allowance balance, individually evaluated for impairment
Ending allowance balance, collectively evaluated for impairment	96		42
Loans and Leases Receivable, Allowance	96	63	42	67
Ending loan balance, individually evaluated for impairment
Ending loan balance, collectively evaluated for impairment	19,936		21,371
Ending loan balance, total	19,936	20,605	21,371
Other [Member] \| Consumer and Other Portfolio Segment [Member]
Ending allowance balance, individually evaluated for impairment
Ending allowance balance, collectively evaluated for impairment	26		358
Loans and Leases Receivable, Allowance	26	19	358	379
Ending loan balance, individually evaluated for impairment
Ending loan balance, collectively evaluated for impairment	19,141		6,049
Ending loan balance, total	19,141	16,492	6,049
Ending allowance balance, individually evaluated for impairment	3,381		767
Ending allowance balance, collectively evaluated for impairment	6,009		7,713
Loans and Leases Receivable, Allowance	9,390	8,604	8,480	$ 8,802
Ending loan balance, individually evaluated for impairment	22,513		29,078
Ending loan balance, collectively evaluated for impairment	741,696		731,000
Ending loan balance, total	$ 764,209	$ 758,636	$ 760,078

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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- Definition

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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