Note 4 - Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Commercial [Member] \| Commercial and Agricultural Portfolio Segment [Member]
Allowance for loan losses, beginning balance	$ 855	$ 497
Allowance for loan losses, charge-offs	(169)	(184)
Allowance for loan losses, recoveries	12	13
Provision for Loan Losses	(144)	8
Allowance for loan losses, ending balance	554	334
Ending allowance balance, individually evaluated for impairment	4	94
Ending allowance balance, collectively evaluated for impairment	550	240
Ending loan balance, individually evaluated for impairment	37	94
Ending loan balance, collectively evaluated for impairment	45,078	51,680
Ending loan balance, total	45,115	51,774	$ 47,782
Commercial [Member] \| Real Estate Portfolio Segment [Member]
Allowance for loan losses, beginning balance	3,851	3,665
Allowance for loan losses, charge-offs	(248)	(125)
Allowance for loan losses, recoveries	168	88
Provision for Loan Losses	1,475	144
Allowance for loan losses, ending balance	5,246	3,772
Ending allowance balance, individually evaluated for impairment	1,940	209
Ending allowance balance, collectively evaluated for impairment	3,306	3,563
Ending loan balance, individually evaluated for impairment	16,918	21,953
Ending loan balance, collectively evaluated for impairment	330,454	319,892
Ending loan balance, total	347,372	341,845	346,262
Agricultural [Member] \| Commercial and Agricultural Portfolio Segment [Member]
Allowance for loan losses, beginning balance	203	$ 304
Allowance for loan losses, charge-offs	(22)
Allowance for loan losses, recoveries	1	$ 1
Provision for Loan Losses	10	2
Allowance for loan losses, ending balance	$ 192	$ 307
Ending allowance balance, individually evaluated for impairment
Ending allowance balance, collectively evaluated for impairment	$ 192	$ 307
Ending loan balance, individually evaluated for impairment		8
Ending loan balance, collectively evaluated for impairment	$ 18,562	19,180
Ending loan balance, total	18,562	19,188	19,193
Commercial Construction [Member] \| Real Estate Portfolio Segment [Member]
Allowance for loan losses, beginning balance	$ 691	1,223
Allowance for loan losses, charge-offs		(6)
Allowance for loan losses, recoveries	$ 804	14
Provision for Loan Losses	(685)	138
Allowance for loan losses, ending balance	810	1,369
Ending allowance balance, individually evaluated for impairment	24	49
Ending allowance balance, collectively evaluated for impairment	786	1,320
Ending loan balance, individually evaluated for impairment	389	3,428
Ending loan balance, collectively evaluated for impairment	35,581	45,183
Ending loan balance, total	35,970	48,611	40,107
Residential Construction [Member] \| Real Estate Portfolio Segment [Member]
Allowance for loan losses, beginning balance	$ 20	$ 138
Allowance for loan losses, charge-offs
Allowance for loan losses, recoveries
Provision for Loan Losses
Allowance for loan losses, ending balance	$ 20	$ 138
Ending allowance balance, individually evaluated for impairment
Ending allowance balance, collectively evaluated for impairment	$ 20	$ 138
Ending loan balance, individually evaluated for impairment
Ending loan balance, collectively evaluated for impairment	$ 9,849	$ 10,030
Ending loan balance, total	9,849	10,030	9,413
Residential [Member] \| Real Estate Portfolio Segment [Member]
Allowance for loan losses, beginning balance	1,990	2,425
Allowance for loan losses, charge-offs	(63)	(589)
Allowance for loan losses, recoveries	14	22
Provision for Loan Losses	(136)	42
Allowance for loan losses, ending balance	1,805	1,900
Ending allowance balance, individually evaluated for impairment	528	330
Ending allowance balance, collectively evaluated for impairment	1,277	1,570
Ending loan balance, individually evaluated for impairment	3,370	3,680
Ending loan balance, collectively evaluated for impairment	192,309	199,198
Ending loan balance, total	195,679	202,878	197,002
Farmland [Member] \| Real Estate Portfolio Segment [Member]
Allowance for loan losses, beginning balance	$ 912	$ 104
Allowance for loan losses, charge-offs
Allowance for loan losses, recoveries	$ 125
Provision for Loan Losses	(234)	$ 2
Allowance for loan losses, ending balance	803	106
Ending allowance balance, individually evaluated for impairment	35	53
Ending allowance balance, collectively evaluated for impairment	768	53
Ending loan balance, individually evaluated for impairment	1,401	1,699
Ending loan balance, collectively evaluated for impairment	64,884	49,873
Ending loan balance, total	66,285	51,572	61,780
Consumer [Member] \| Consumer and Other Portfolio Segment [Member]
Allowance for loan losses, beginning balance	63	67
Allowance for loan losses, charge-offs	(49)	(36)
Allowance for loan losses, recoveries	15	13
Provision for Loan Losses	72	26
Allowance for loan losses, ending balance	$ 101	$ 70
Ending allowance balance, individually evaluated for impairment
Ending allowance balance, collectively evaluated for impairment	$ 101	$ 70
Ending loan balance, individually evaluated for impairment
Ending loan balance, collectively evaluated for impairment	$ 19,661	$ 21,705
Ending loan balance, total	19,661	21,705	20,605
Other [Member] \| Consumer and Other Portfolio Segment [Member]
Allowance for loan losses, beginning balance	$ 19	$ 379
Allowance for loan losses, charge-offs
Allowance for loan losses, recoveries	$ 3	$ 2
Provision for Loan Losses	(4)
Allowance for loan losses, ending balance	$ 18	$ 381
Ending allowance balance, individually evaluated for impairment
Ending allowance balance, collectively evaluated for impairment	$ 18	$ 381
Ending loan balance, individually evaluated for impairment
Ending loan balance, collectively evaluated for impairment	$ 15,768	$ 6,031
Ending loan balance, total	15,768	6,031	16,492
Allowance for loan losses, beginning balance	8,604	8,802
Allowance for loan losses, charge-offs	(551)	(940)
Allowance for loan losses, recoveries	1,142	153
Provision for Loan Losses	354	362
Allowance for loan losses, ending balance	9,549	8,377
Ending allowance balance, individually evaluated for impairment	2,531	735
Ending allowance balance, collectively evaluated for impairment	7,018	7,642
Ending loan balance, individually evaluated for impairment	22,115	30,862
Ending loan balance, collectively evaluated for impairment	732,146	722,772
Ending loan balance, total	$ 754,261	$ 753,634	$ 758,636

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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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)
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-Publisher FASB
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-Topic 942
-SubTopic 210
-Section S99
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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
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Amount of expense related to estimated loss from loan and lease transactions.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 225
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