Note 4 - Loans and the Allowance for Loan Losses - Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Beginning balance	$ 8,835	$ 7,058	$ 7,243	$ 6,958	$ 6,958
Provision charged to operations	800	300	2,800	900	1,500
Charge-offs	(133)	(217)	(668)	(874)	(1,521)
Recoveries	98	85	225	242	306
Ending balance	$ 9,600	$ 7,226	$ 9,600	$ 7,226	$ 7,243

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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