Note 7 - Loans Receivable and Credit Disclosures - Activity in Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Balance	$ 17,215	$ 12,619
Provision (credit) for loan losses	(426)	2,316
Recoveries of loans charged-off	269	7
Loans charged-off	(151)	(33)
Balance	16,907	14,909
Construction Real Estate [Member]
Balance	725	672
Provision (credit) for loan losses	143	80
Recoveries of loans charged-off	0	1
Loans charged-off	0	0
Balance	868	753
Family Residential Real Estate 1-4 [Member]
Balance	2,581	2,122
Provision (credit) for loan losses	(431)	214
Recoveries of loans charged-off	263	0
Loans charged-off	(30)	0
Balance	2,383	2,336
Commercial Real Estate Portfolio Segment [Member]
Balance	8,930	5,362
Provision (credit) for loan losses	118	1,220
Recoveries of loans charged-off	1	1
Loans charged-off	0	(31)
Balance	9,049	6,552
Agriculture Real Estate [Member]
Balance	1,595	1,326
Provision (credit) for loan losses	(97)	237
Recoveries of loans charged-off	0	0
Loans charged-off	0	0
Balance	1,498	1,563
Commercial Portfolio Segment [Member]
Balance	1,453	1,458
Provision (credit) for loan losses	(79)	212
Recoveries of loans charged-off	1	2
Loans charged-off	(113)	0
Balance	1,262	1,672
Agriculture [Member]
Balance	1,696	1,478
Provision (credit) for loan losses	(82)	337
Recoveries of loans charged-off	0	0
Loans charged-off	0	0
Balance	1,614	1,815
Consumer and Other [Member]
Balance	235	201
Provision (credit) for loan losses	2	16
Recoveries of loans charged-off	4	3
Loans charged-off	(8)	(2)
Balance	$ 233	$ 218

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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