Note 8 - Loans and Related Allowance for Loan and Lease Losses - Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Dec. 31, 2019
Individually evaluated for impairment			$ 1,216	$ 660
Collectively evaluated for impairment			8,028	6,108
Less: allowance for loan and lease losses	$ 6,768	$ 7,206	9,244	6,768
Beginning balance	6,768	7,428
Charge-offs	(508)	(517)
Recoveries	244	55
Provision	2,740	240
Ending balance	9,244	7,206
Commercial Real Estate Portfolio Segment [Member] \| Owner Occupied Loan [Member]
Individually evaluated for impairment			53	45
Collectively evaluated for impairment			1,046	756
Less: allowance for loan and lease losses	801	830	1,099	801
Beginning balance	801	1,315
Charge-offs		(32)
Recoveries	3	1
Provision	295	(454)
Ending balance	1,099	830
Commercial Real Estate Portfolio Segment [Member] \| Non-owner occupied Loan [Member]
Individually evaluated for impairment			1,095	582
Collectively evaluated for impairment			3,269	2,800
Less: allowance for loan and lease losses	3,382	2,857	4,364	3,382
Beginning balance	3,382	2,862
Charge-offs
Recoveries	74
Provision	908	(5)
Ending balance	4,364	2,857
Commercial Real Estate Portfolio Segment [Member] \| Multifamily Loan [Member]
Individually evaluated for impairment
Collectively evaluated for impairment			386	340
Less: allowance for loan and lease losses	340	492	386	340
Beginning balance	340	474
Charge-offs
Recoveries
Provision	46	18
Ending balance	386	492
Residential Portfolio Segment [Member]
Individually evaluated for impairment			25	28
Collectively evaluated for impairment			1,139	698
Less: allowance for loan and lease losses	726	773	1,164	726
Beginning balance	726	761
Charge-offs	(46)
Recoveries	29	10
Provision	455	2
Ending balance	1,164	773
Commercial And Industrial [Member]
Individually evaluated for impairment			3	3
Collectively evaluated for impairment			713	453
Less: allowance for loan and lease losses	456	586	716	456
Beginning balance	456	969
Charge-offs	(61)	(347)
Recoveries	109	16
Provision	212	(52)
Ending balance	716	586
Home Equity Lines of Credit [Member]
Individually evaluated for impairment			40	2
Collectively evaluated for impairment			1,200	930
Less: allowance for loan and lease losses	932	832	1,240	932
Beginning balance	932	820
Charge-offs	(13)	(91)
Recoveries	3	4
Provision	318	99
Ending balance	1,240	832
Construction and Other [Member]
Individually evaluated for impairment
Collectively evaluated for impairment			254	103
Less: allowance for loan and lease losses	103	748	254	103
Beginning balance	103	100
Charge-offs
Recoveries	17	23
Provision	134	625
Ending balance	254	748
Consumer Portfolio Segment [Member]
Individually evaluated for impairment
Collectively evaluated for impairment			21	28
Less: allowance for loan and lease losses	28	88	$ 21	$ 28
Beginning balance	28	127
Charge-offs	(388)	(47)
Recoveries	9	1
Provision	372	7
Ending balance	$ 21	$ 88

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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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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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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