Note 4 - Allowance for Loan Losses - Segregated by Class of Loan (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Allowance for loan losses, beginning balance			$ 7,508	$ 8,923
Allowance for loan losses, charge-offs			(837)	(2,283)
Allowance for loan losses, recoveries			353	1,002
Provision for Loan Losses	$ 61		131	335
Allowance for loan losses, ending balance	7,155	7,977	7,155	7,977
Allowance for loan losses, provision	61		131	335
Commercial [Member] \| Commercial and Agricultural Portfolio Segment [Member]
Allowance for loan losses, beginning balance			447	456
Allowance for loan losses, charge-offs			(118)	(215)
Allowance for loan losses, recoveries			114	124
Provision for Loan Losses			(59)	71
Allowance for loan losses, ending balance	384	436	384	436
Allowance for loan losses, provision			(59)	71
Commercial [Member] \| Real Estate Portfolio Segment [Member]
Allowance for loan losses, beginning balance			3,874	5,751
Allowance for loan losses, charge-offs			(258)	(966)
Allowance for loan losses, recoveries			39	523
Provision for Loan Losses			626	(1,085)
Allowance for loan losses, ending balance	4,281	4,223	4,281	4,223
Allowance for loan losses, provision			626	(1,085)
Agricultural [Member] \| Commercial and Agricultural Portfolio Segment [Member]
Allowance for loan losses, beginning balance			186	168
Allowance for loan losses, charge-offs			(123)	(160)
Allowance for loan losses, recoveries			7	3
Provision for Loan Losses			245	238
Allowance for loan losses, ending balance	315	249	315	249
Allowance for loan losses, provision			245	238
Commercial Construction [Member] \| Real Estate Portfolio Segment [Member]
Allowance for loan losses, beginning balance			1,216	323
Allowance for loan losses, charge-offs			0	(49)
Allowance for loan losses, recoveries			39	241
Provision for Loan Losses			(1,130)	473
Allowance for loan losses, ending balance	125	988	125	988
Allowance for loan losses, provision			(1,130)	473
Residential Construction [Member] \| Real Estate Portfolio Segment [Member]
Allowance for loan losses, beginning balance				13
Allowance for loan losses, charge-offs			0	0
Allowance for loan losses, recoveries			0	0
Provision for Loan Losses			17	(7)
Allowance for loan losses, ending balance	17	6	17	6
Allowance for loan losses, provision			17	(7)
Residential [Member] \| Real Estate Portfolio Segment [Member]
Allowance for loan losses, beginning balance			968	1,396
Allowance for loan losses, charge-offs			(124)	(648)
Allowance for loan losses, recoveries			83	47
Provision for Loan Losses			255	334
Allowance for loan losses, ending balance	1,182	1,129	1,182	1,129
Allowance for loan losses, provision			255	334
Farmland [Member] \| Real Estate Portfolio Segment [Member]
Allowance for loan losses, beginning balance			780	722
Allowance for loan losses, charge-offs			0	(61)
Allowance for loan losses, recoveries			11	2
Provision for Loan Losses			(61)	209
Allowance for loan losses, ending balance	730	872	730	872
Allowance for loan losses, provision			(61)	209
Consumer [Member] \| Consumer and Other Portfolio Segment [Member]
Allowance for loan losses, beginning balance			34	80
Allowance for loan losses, charge-offs			(214)	(184)
Allowance for loan losses, recoveries			59	60
Provision for Loan Losses			214	100
Allowance for loan losses, ending balance	93	56	93	56
Allowance for loan losses, provision			214	100
Other [Member] \| Consumer and Other Portfolio Segment [Member]
Allowance for loan losses, beginning balance			3	14
Allowance for loan losses, charge-offs				0
Allowance for loan losses, recoveries			1	2
Provision for Loan Losses			24	2
Allowance for loan losses, ending balance	$ 28	$ 18	28	18
Allowance for loan losses, provision			$ 24	$ 2

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.

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

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