Note 4 - Loans and Allowance for Loan Losses - Activity in the Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Beginning Balance	$ 9,867	$ 9,558
Charge-offs	(124)	(213)
Recoveries	79	42
Provision	2,500	25
Ending Balance	12,322	9,412
Individually Evaluated for Impairment	651	983	$ 884
Collectively Evaluated for Potential Impairment	11,671	8,429	8,983
Residential Portfolio Segment [Member] \| Real Estate Sector [Member]
Beginning Balance	2,023	1,050
Charge-offs	(25)
Recoveries	2	4
Provision	685	100
Ending Balance	2,685	1,154
Individually Evaluated for Impairment
Collectively Evaluated for Potential Impairment	2,685	1,154	2,023
Commercial Portfolio Segment [Member] \| Real Estate Sector [Member]
Beginning Balance	3,210	2,693
Charge-offs
Recoveries	14	13
Provision	1,651	(156)
Ending Balance	4,875	2,550
Individually Evaluated for Impairment	392	199	274
Collectively Evaluated for Potential Impairment	4,483	2,351	2,936
Commercial Portfolio Segment [Member] \| Commercial and Industrial Sector [Member]
Beginning Balance	2,412	2,807
Charge-offs
Recoveries	9	1
Provision	(829)	(255)
Ending Balance	1,592	2,553
Individually Evaluated for Impairment	259	784	610
Collectively Evaluated for Potential Impairment	1,333	1,769	1,802
Construction Portfolio Segment [Member] \| Real Estate Sector [Member]
Beginning Balance	285	395
Charge-offs
Recoveries
Provision	379	105
Ending Balance	664	500
Individually Evaluated for Impairment
Collectively Evaluated for Potential Impairment	664	500	285
Consumer Portfolio Segment [Member]
Beginning Balance	1,417	2,027
Charge-offs	(99)	(213)
Recoveries	54	24
Provision	507	(105)
Ending Balance	1,879	1,733
Individually Evaluated for Impairment
Collectively Evaluated for Potential Impairment	1,879	1,733	1,417
Other Portfolio Segment [Member]
Beginning Balance
Charge-offs
Recoveries
Provision
Ending Balance
Individually Evaluated for Impairment
Collectively Evaluated for Potential Impairment
Unallocated Financing Receivables [Member]
Beginning Balance	520	586
Charge-offs
Recoveries
Provision	107	336
Ending Balance	627	922
Individually Evaluated for Impairment
Collectively Evaluated for Potential Impairment	$ 627	$ 922	$ 520

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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