Note 6 - Loans Receivable and Allowance for Loan Losses - Impaired Loans, Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
With no related allowance recorded - Average recorded investment	$ 14,478	$ 13,197	$ 14,066	$ 11,641
With no related allowance recorded - Interest income recognized	88	116	243	293
With related allowance - Average recorded investment	5,033	6,190	5,935	6,270
With related allowance - Interest income recognized	1	12	18	24
Average recorded investment	19,511	19,387	20,001	17,911
Interest income recognized	89	128	261	317
Commercial Real Estate Portfolio Segment [Member]
With no related allowance recorded - Average recorded investment	6,534	7,004	6,484	6,532
With no related allowance recorded - Interest income recognized	69	80	207	220
With related allowance - Average recorded investment	4,167	4,114	4,153	4,314
With related allowance - Interest income recognized	0	0	0	0
Average recorded investment	10,701	11,118	10,637	10,846
Interest income recognized	69	80	207	220
Construction and Land Development Portfolio Segment [Member]
With no related allowance recorded - Average recorded investment	0	0	0	0
With no related allowance recorded - Interest income recognized	0	0	0	0
With related allowance - Average recorded investment	0	0	0	0
With related allowance - Interest income recognized	0	0	0	0
Average recorded investment	0	0	0	0
Interest income recognized	0	0	0	0
Commercial Portfolio Segment [Member]
With no related allowance recorded - Average recorded investment	2,615	2,821	2,607	2,001
With no related allowance recorded - Interest income recognized	0	19	1	19
With related allowance - Average recorded investment	37	572	479	956
With related allowance - Interest income recognized	0	0	0	0
Average recorded investment	2,652	3,393	3,086	2,957
Interest income recognized	0	19	1	19
Owner Occupied Real Estate [Member]
With no related allowance recorded - Average recorded investment	3,491	1,801	3,051	1,853
With no related allowance recorded - Interest income recognized	13	12	21	40
With related allowance - Average recorded investment	819	1,492	1,273	962
With related allowance - Interest income recognized	1	12	17	24
Average recorded investment	4,310	3,293	4,324	2,815
Interest income recognized	14	24	38	64
Consumer Portfolio Segment [Member]
With no related allowance recorded - Average recorded investment	1,114	931	1,156	871
With no related allowance recorded - Interest income recognized	6	4	13	12
With related allowance - Average recorded investment	10	12	0	38
With related allowance - Interest income recognized	0	0	0	0
Average recorded investment	1,124	943	1,156	909
Interest income recognized	6	4	13	12
Residential Portfolio Segment [Member]
With no related allowance recorded - Average recorded investment	724	640	768	384
With no related allowance recorded - Interest income recognized	0	1	1	2
With related allowance - Average recorded investment	0	0	30	0
With related allowance - Interest income recognized	0	0	1	0
Average recorded investment	724	640	798	384
Interest income recognized	0	1	2	2
Paycheck Protection Program CARES Act [Member]
With no related allowance recorded - Average recorded investment	0	0	0	0
With no related allowance recorded - Interest income recognized	0	0	0	0
With related allowance - Average recorded investment	0	0	0	0
With related allowance - Interest income recognized	0	0	0	0
Average recorded investment	0	0	0	0
Interest income recognized	$ 0	$ 0	$ 0	$ 0

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5212-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5258-111524

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+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5258-111524

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+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 19
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5278-111524

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