Note 4 - Loans and Allowance for Loan Losses - Allowance for Loan Losses Activity by Portfolio Segment (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Balance	$ 6,272	$ 6,728
Provision for loan losses	3,846	2,378
Loans charged off	(1,636)	(1,361)
Recoveries	247	268
Balance	8,729	8,013
Residential Portfolio Segment [Member]
Balance	1,250	1,583
Provision for loan losses	926	813
Loans charged off	(198)	(329)
Recoveries	24	12
Balance	2,002	2,079
Commercial Real Estate Portfolio Segment [Member]
Balance	1,928	2,186
Provision for loan losses	1,572	393
Loans charged off	(516)	(141)
Recoveries	44	14
Balance	3,028	2,452
Commercial and Industrial Portfolio Segment [Member]
Balance	1,447	1,063
Provision for loan losses	624	473
Loans charged off	(33)	(233)
Recoveries	7	12
Balance	2,045	1,315
Consumer Portfolio Segment [Member]
Balance	1,647	1,896
Provision for loan losses	724	699
Loans charged off	(889)	(658)
Recoveries	172	230
Balance	$ 1,654	$ 2,167