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Note 8 - Loans and Related Allowance for Loan and Lease Losses - Impaired Loans by Class (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Recorded investment, with no related allowance	$ 11,576	$ 7,344
Unpaid principal balance, with no related allowance	12,234	8,199
Recorded investment, with related allowance	4,959	5,726
Unpaid principal balance, with related allowance	5,233	5,787
Related allowance	515	660
Recorded investment	16,535	13,070
Unpaid principal balance	17,467	13,986
Commercial Real Estate Portfolio Segment [Member] | Owner Occupied Loan [Member]
Recorded investment, with no related allowance	1,844	1,772
Unpaid principal balance, with no related allowance	1,863	1,772
Recorded investment, with related allowance	456	1,702
Unpaid principal balance, with related allowance	456	1,713
Related allowance	10	45
Recorded investment	2,300	3,474
Unpaid principal balance	2,319	3,485
Commercial Real Estate Portfolio Segment [Member] | Non-owner occupied Loan [Member]
Recorded investment, with no related allowance	7,518	3,845
Unpaid principal balance, with no related allowance	7,518	3,845
Recorded investment, with related allowance	3,620	3,239
Unpaid principal balance, with related allowance	3,894	3,239
Related allowance	403	582
Recorded investment	11,138	7,084
Unpaid principal balance	11,412	7,084
Residential Portfolio Segment [Member]
Recorded investment, with no related allowance	797	759
Unpaid principal balance, with no related allowance	927	829
Recorded investment, with related allowance	428	519
Unpaid principal balance, with related allowance	428	569
Related allowance	21	28
Recorded investment	1,225	1,278
Unpaid principal balance	1,355	1,398
Commercial And Industrial [Member]
Recorded investment, with no related allowance	1,336	747
Unpaid principal balance, with no related allowance	1,833	1,524
Recorded investment, with related allowance	288	135
Unpaid principal balance, with related allowance	288	135
Related allowance	60	3
Recorded investment	1,624	882
Unpaid principal balance	2,121	1,659
Home Equity Lines of Credit [Member]
Recorded investment, with no related allowance	81	220
Unpaid principal balance, with no related allowance	93	228
Recorded investment, with related allowance	167	131
Unpaid principal balance, with related allowance	167	131
Related allowance	21	2
Recorded investment	248	351
Unpaid principal balance	$ 260	359
Consumer Portfolio Segment [Member]
Recorded investment, with no related allowance		1
Unpaid principal balance, with no related allowance		1
Related allowance		0
Recorded investment		1
Unpaid principal balance		$ 1

X

- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953550-111524

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X

- Definition

Amount of allowance for credit losses related to recorded investment.

+ References

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 (a)(3)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5212-111524

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X

- Definition

Amount of unpaid principal balance of impaired financing receivables with related allowance for credit losses and without related allowance for credit losses.

+ References

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 (a)(4)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5212-111524

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- Definition

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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 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953550-111524

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- Definition

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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 15
-Subparagraph (a)(4)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5212-111524

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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 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953550-111524

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- Definition

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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 15
-Subparagraph (a)(4)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5212-111524

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