Note 5 - Allowance for Loan Losses - Segregated by Class of Loan (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Allowance for loan losses, beginning balance			$ 7,277	$ 7,508
Allowance for loan losses, charge-offs			(1,687)	(837)
Allowance for loan losses, recoveries			486	353
Allowance for loan losses, provision	$ 214	$ 61	524	131
Allowance for loan losses, ending balance	6,600	7,155	6,600	7,155
Provision for Loan Losses	214	61	524	131
Provision for Loan Losses	214	61	524	131
Commercial [Member] \| Commercial and Agricultural Portfolio Segment [Member]
Allowance for loan losses, beginning balance			370	447
Allowance for loan losses, charge-offs			(266)	(118)
Allowance for loan losses, recoveries			27	114
Allowance for loan losses, provision			312	(59)
Allowance for loan losses, ending balance	443	384	443	384
Provision for Loan Losses			312	(59)
Provision for Loan Losses			312	(59)
Commercial [Member] \| Real Estate Portfolio Segment [Member]
Allowance for loan losses, beginning balance			4,549	3,874
Allowance for loan losses, charge-offs			(56)	(258)
Allowance for loan losses, recoveries			173	39
Allowance for loan losses, provision			(1,376)	626
Allowance for loan losses, ending balance	3,290	4,281	3,290	4,281
Provision for Loan Losses			(1,376)	626
Provision for Loan Losses			(1,376)	626
Agricultural [Member] \| Commercial and Agricultural Portfolio Segment [Member]
Allowance for loan losses, beginning balance			248	186
Allowance for loan losses, charge-offs			(84)	(123)
Allowance for loan losses, recoveries			4	7
Allowance for loan losses, provision			703	245
Allowance for loan losses, ending balance	871	315	871	315
Provision for Loan Losses			703	245
Provision for Loan Losses			703	245
Commercial Construction [Member] \| Real Estate Portfolio Segment [Member]
Allowance for loan losses, beginning balance			115	1,216
Allowance for loan losses, charge-offs			(29)
Allowance for loan losses, recoveries			61	39
Allowance for loan losses, provision			(5)	(1,130)
Allowance for loan losses, ending balance	142	125	142	125
Provision for Loan Losses			(5)	(1,130)
Provision for Loan Losses			(5)	(1,130)
Residential Construction [Member] \| Real Estate Portfolio Segment [Member]
Allowance for loan losses, beginning balance			16
Allowance for loan losses, charge-offs			0	0
Allowance for loan losses, recoveries			0	0
Allowance for loan losses, provision			17	17
Allowance for loan losses, ending balance	33	17	33	17
Provision for Loan Losses			17	17
Provision for Loan Losses			17	17
Residential [Member] \| Real Estate Portfolio Segment [Member]
Allowance for loan losses, beginning balance			1,181	968
Allowance for loan losses, charge-offs			(757)	(124)
Allowance for loan losses, recoveries			166	83
Allowance for loan losses, provision			367	255
Allowance for loan losses, ending balance	957	1,182	957	1,182
Provision for Loan Losses			367	255
Provision for Loan Losses			367	255
Farmland [Member] \| Real Estate Portfolio Segment [Member]
Allowance for loan losses, beginning balance			702	780
Allowance for loan losses, charge-offs			(63)
Allowance for loan losses, recoveries			10	11
Allowance for loan losses, provision			74	(61)
Allowance for loan losses, ending balance	723	730	723	730
Provision for Loan Losses			74	(61)
Provision for Loan Losses			74	(61)
Consumer [Member] \| Consumer and Other Portfolio Segment [Member]
Allowance for loan losses, beginning balance			86	34
Allowance for loan losses, charge-offs			(432)	(214)
Allowance for loan losses, recoveries			41	59
Allowance for loan losses, provision			404	214
Allowance for loan losses, ending balance	99	93	99	93
Provision for Loan Losses			404	214
Provision for Loan Losses			404	214
Other [Member] \| Consumer and Other Portfolio Segment [Member]
Allowance for loan losses, beginning balance			10	3
Allowance for loan losses, charge-offs			0
Allowance for loan losses, recoveries			4	1
Allowance for loan losses, provision			28	24
Allowance for loan losses, ending balance	$ 42	$ 28	42	28
Provision for Loan Losses			28	24
Provision for Loan Losses			$ 28	$ 24

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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