Note 5 - Allowance for Loan Losses - Segregated by Class of Loan (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Allowance for loan losses, beginning balance			$ 7,277	$ 7,508
Allowance for loan losses, charge-offs			(1,099)	(721)
Allowance for loan losses, recoveries			301	302
Allowance for loan losses, provision	$ 179	$ 44	310	70
Allowance for loan losses, ending balance	6,789	7,159	6,789	7,159
Provision for Loan Losses	179	44	310	70
Provision for Loan Losses	179	44	310	70
Commercial [Member] \| Commercial and Agricultural Portfolio Segment [Member]
Allowance for loan losses, beginning balance			370	447
Allowance for loan losses, charge-offs			(125)	(116)
Allowance for loan losses, recoveries			16	85
Allowance for loan losses, provision			122	28
Allowance for loan losses, ending balance	383	444	383	444
Provision for Loan Losses			122	28
Provision for Loan Losses			122	28
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			38	37
Allowance for loan losses, provision			(790)	753
Allowance for loan losses, ending balance	3,741	4,406	3,741	4,406
Provision for Loan Losses			(790)	753
Provision for Loan Losses			(790)	753
Agricultural [Member] \| Commercial and Agricultural Portfolio Segment [Member]
Allowance for loan losses, beginning balance			248	186
Allowance for loan losses, charge-offs			0	(123)
Allowance for loan losses, recoveries			1	7
Allowance for loan losses, provision			789	192
Allowance for loan losses, ending balance	1,038	262	1,038	262
Provision for Loan Losses			789	192
Provision for Loan Losses			789	192
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			54	38
Allowance for loan losses, provision			(130)	(1,172)
Allowance for loan losses, ending balance	10	82	10	82
Provision for Loan Losses			(130)	(1,172)
Provision for Loan Losses			(130)	(1,172)
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			(14)
Allowance for loan losses, ending balance	2		2
Provision for Loan Losses			(14)
Provision for Loan Losses			(14)
Residential [Member] \| Real Estate Portfolio Segment [Member]
Allowance for loan losses, beginning balance			1,181	968
Allowance for loan losses, charge-offs			(647)	(89)
Allowance for loan losses, recoveries			159	75
Allowance for loan losses, provision			152	112
Allowance for loan losses, ending balance	845	1,066	845	1,066
Provision for Loan Losses			152	112
Provision for Loan Losses			152	112
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			3	9
Allowance for loan losses, provision			47	79
Allowance for loan losses, ending balance	689	868	689	868
Provision for Loan Losses			47	79
Provision for Loan Losses			47	79
Consumer [Member] \| Consumer and Other Portfolio Segment [Member]
Allowance for loan losses, beginning balance			86	34
Allowance for loan losses, charge-offs			(179)	(135)
Allowance for loan losses, recoveries			27	49
Allowance for loan losses, provision			129	82
Allowance for loan losses, ending balance	63	30	63	30
Provision for Loan Losses			129	82
Provision for Loan Losses			129	82
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			3	2
Allowance for loan losses, provision			5	(4)
Allowance for loan losses, ending balance	$ 18	$ 1	18	1
Provision for Loan Losses			5	(4)
Provision for Loan Losses			$ 5	$ (4)

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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