Note 5 - Loans and Leases - Summary of the Activity in the Allowance for Loan and Lease Losses of Impaired Loans (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Allowance for loan and lease losses beginning balance	$ 3,527	$ 2,835	$ 3,345
Provision for loan and lease losses	550	450	(350)
Losses charged off	(180)	(197)	(689)
Recoveries	234	439	529
Allowance for loan and lease losses ending balance	4,131	3,527	2,835
Impaired Loans [Member]
Allowance for loan and lease losses beginning balance	128		1,018
Provision for loan and lease losses	307	128	(865)
Losses charged off			(414)
Recoveries			261
Allowance for loan and lease losses ending balance	$ 435	$ 128

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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