Note 8 - Loans and Related Allowance for Loan and Lease Losses - Allowance for Loan Losses (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Jun. 30, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Dec. 31, 2018
Individually evaluated for impairment	$ 515		$ 660
Collectively evaluated for impairment	10,844		6,108
Less: allowance for loan and lease losses	11,359	$ 10,210	6,768	$ 7,001	$ 7,304	$ 7,428
Commercial Real Estate Portfolio Segment [Member] \| Owner Occupied Loan [Member]
Individually evaluated for impairment	10		45
Collectively evaluated for impairment	1,093		756
Less: allowance for loan and lease losses	1,103	1,038	801	837	866	1,315
Commercial Real Estate Portfolio Segment [Member] \| Non-owner occupied Loan [Member]
Individually evaluated for impairment	403		582
Collectively evaluated for impairment	5,002		2,800
Less: allowance for loan and lease losses	5,405	5,159	3,382	3,484	3,588	2,862
Commercial Real Estate Portfolio Segment [Member] \| Multifamily Loan [Member]
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	346		340
Less: allowance for loan and lease losses	346	291	340	389	412	474
Residential Portfolio Segment [Member]
Individually evaluated for impairment	21		28
Collectively evaluated for impairment	1,350		698
Less: allowance for loan and lease losses	1,371	1,167	726	732	747	761
Commercial And Industrial [Member]
Individually evaluated for impairment	60		3
Collectively evaluated for impairment	1,443		453
Less: allowance for loan and lease losses	1,503	1,105	456	389	539	969
Home Equity Lines of Credit [Member]
Individually evaluated for impairment	21		2
Collectively evaluated for impairment	1,305		930
Less: allowance for loan and lease losses	1,326	1,203	932	941	936	820
Construction and Other [Member]
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	293		103
Less: allowance for loan and lease losses	293	236	103	105	97	100
Consumer Portfolio Segment [Member]
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	12		28
Less: allowance for loan and lease losses	$ 12	$ 11	$ 28	$ 124	$ 119	$ 127

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953423-111524

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-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=27010918&loc=d3e74567-122707

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