Note 4 - Allowance for Loan Losses - Segregated by Class of Loan (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Provision for Loan Losses		$ 354	$ 335	$ 708
Allowance for loan losses, ending balance	8,043	9,390	8,043	9,390
Allowance for loan losses, beginning balance			8,923	8,604
Allowance for loan losses, charge-offs			(1,865)	(1,107)
Allowance for loan losses, recoveries			650	1,185
Commercial [Member] \| Commercial and Agricultural Portfolio Segment [Member]
Provision for Loan Losses			(7)	(100)
Allowance for loan losses, ending balance	425	555	425	555
Allowance for loan losses, beginning balance			456	855
Allowance for loan losses, charge-offs			(124)	(225)
Allowance for loan losses, recoveries			100	25
Commercial [Member] \| Real Estate Portfolio Segment [Member]
Provision for Loan Losses			(424)	2,136
Allowance for loan losses, ending balance	4,663	5,598	4,663	5,598
Allowance for loan losses, beginning balance			5,751	3,851
Allowance for loan losses, charge-offs			(966)	(569)
Allowance for loan losses, recoveries			302	180
Agricultural [Member] \| Commercial and Agricultural Portfolio Segment [Member]
Provision for Loan Losses			72	64
Allowance for loan losses, ending balance	238	251	238	251
Allowance for loan losses, beginning balance			168	203
Allowance for loan losses, charge-offs			(4)	(18)
Allowance for loan losses, recoveries			2	2
Commercial Construction [Member] \| Real Estate Portfolio Segment [Member]
Provision for Loan Losses			334	(1,032)
Allowance for loan losses, ending balance	770	438	770	438
Allowance for loan losses, beginning balance			323	691
Allowance for loan losses, charge-offs			(49)	(25)
Allowance for loan losses, recoveries			162	804
Residential Construction [Member] \| Real Estate Portfolio Segment [Member]
Provision for Loan Losses			(2)	(2)
Allowance for loan losses, ending balance	11	18	11	18
Allowance for loan losses, beginning balance			13	20
Allowance for loan losses, charge-offs
Allowance for loan losses, recoveries
Residential [Member] \| Real Estate Portfolio Segment [Member]
Provision for Loan Losses			148	(242)
Allowance for loan losses, ending balance	972	1,612	972	1,612
Allowance for loan losses, beginning balance			1,396	1,990
Allowance for loan losses, charge-offs			(605)	(159)
Allowance for loan losses, recoveries			33	23
Farmland [Member] \| Real Estate Portfolio Segment [Member]
Provision for Loan Losses			137	(241)
Allowance for loan losses, ending balance	859	796	859	796
Allowance for loan losses, beginning balance			722	912
Allowance for loan losses, charge-offs
Allowance for loan losses, recoveries				125
Consumer [Member] \| Consumer and Other Portfolio Segment [Member]
Provision for Loan Losses			70	123
Allowance for loan losses, ending balance	84	96	84	96
Allowance for loan losses, beginning balance			80	63
Allowance for loan losses, charge-offs			(117)	(111)
Allowance for loan losses, recoveries			51	21
Other [Member] \| Consumer and Other Portfolio Segment [Member]
Provision for Loan Losses			7	2
Allowance for loan losses, ending balance	$ 21	$ 26	21	26
Allowance for loan losses, beginning balance			14	19
Allowance for loan losses, charge-offs
Allowance for loan losses, recoveries				$ 5

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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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
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-Publisher FASB
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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
-Topic 942
-SubTopic 225
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