Note 4 - Allowance for Loan Losses - Segregated by Class of Loan (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Allowance for loan losses, beginning balance			$ 8,923	$ 8,604
Allowance for loan losses, charge-offs			(2,283)	(1,749)
Allowance for loan losses, recoveries			1,002	1,286
Allowance for loan losses, provision		$ 354	335	1,062
Allowance for loan losses, ending balance	7,977	9,203	7,977	9,203
Commercial [Member] \| Commercial and Agricultural Portfolio Segment [Member]
Allowance for loan losses, beginning balance			456	855
Allowance for loan losses, charge-offs			(215)	(291)
Allowance for loan losses, recoveries			124	54
Allowance for loan losses, provision			71	(127)
Allowance for loan losses, ending balance	436	491	436	491
Commercial [Member] \| Real Estate Portfolio Segment [Member]
Allowance for loan losses, beginning balance			5,751	3,851
Allowance for loan losses, charge-offs			(966)	(992)
Allowance for loan losses, recoveries			523	197
Allowance for loan losses, provision			(1,085)	2,231
Allowance for loan losses, ending balance	4,223	5,287	4,223	5,287
Agricultural [Member] \| Commercial and Agricultural Portfolio Segment [Member]
Allowance for loan losses, beginning balance			168	203
Allowance for loan losses, charge-offs			(160)	(18)
Allowance for loan losses, recoveries			3	3
Allowance for loan losses, provision			238	93
Allowance for loan losses, ending balance	249	281	249	281
Commercial Construction [Member] \| Real Estate Portfolio Segment [Member]
Allowance for loan losses, beginning balance			323	691
Allowance for loan losses, charge-offs			(49)	(25)
Allowance for loan losses, recoveries			241	813
Allowance for loan losses, provision			473	(1,021)
Allowance for loan losses, ending balance	988	458	988	458
Residential Construction [Member] \| Real Estate Portfolio Segment [Member]
Allowance for loan losses, beginning balance			13	20
Allowance for loan losses, charge-offs
Allowance for loan losses, recoveries
Allowance for loan losses, provision			(7)	2
Allowance for loan losses, ending balance	6	22	6	22
Residential [Member] \| Real Estate Portfolio Segment [Member]
Allowance for loan losses, beginning balance			1,396	1,990
Allowance for loan losses, charge-offs			(648)	(243)
Allowance for loan losses, recoveries			47	32
Allowance for loan losses, provision			334	(114)
Allowance for loan losses, ending balance	1,129	1,665	1,129	1,665
Farmland [Member] \| Real Estate Portfolio Segment [Member]
Allowance for loan losses, beginning balance			722	912
Allowance for loan losses, charge-offs			(61)
Allowance for loan losses, recoveries			2	137
Allowance for loan losses, provision			209	(187)
Allowance for loan losses, ending balance	872	862	872	862
Consumer [Member] \| Consumer and Other Portfolio Segment [Member]
Allowance for loan losses, beginning balance			80	63
Allowance for loan losses, charge-offs			(184)	(180)
Allowance for loan losses, recoveries			60	44
Allowance for loan losses, provision			100	176
Allowance for loan losses, ending balance	56	103	56	103
Other [Member] \| Consumer and Other Portfolio Segment [Member]
Allowance for loan losses, beginning balance			14	19
Allowance for loan losses, charge-offs
Allowance for loan losses, recoveries			2	6
Allowance for loan losses, provision			2	9
Allowance for loan losses, ending balance	$ 18	$ 34	$ 18	$ 34

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

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Amount of expense related to estimated loss from loan and lease transactions.

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