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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, 2019	Dec. 31, 2018
Recorded investment, with no related allowance	$ 4,996	$ 3,380
Unpaid principal balance, with no related allowance	6,027	4,061
Recorded investment, with related allowance	9,503	10,695
Unpaid principal balance, with related allowance	9,562	11,406
Related allowance	706	1,354
Recorded investment	14,499	14,075
Unpaid principal balance	15,589	15,467
Commercial Loans [Member]
Recorded investment, with related allowance	8,700
Unpaid principal balance, with related allowance	8,710
Related allowance	670
Commercial And Industrial [Member]
Recorded investment, with no related allowance	1,308	207
Unpaid principal balance, with no related allowance	2,059	413
Recorded investment, with related allowance	149	2,363
Unpaid principal balance, with related allowance	149	3,013
Related allowance	3	667
Recorded investment	1,457	2,570
Unpaid principal balance	2,208	3,426
Real Estate Mortgage Portfolio Segment [Member] | Residential Loan [Member]
Recorded investment, with no related allowance	1,126	1,306
Unpaid principal balance, with no related allowance	1,406	1,462
Recorded investment, with related allowance		664
Unpaid principal balance, with related allowance		715
Related allowance	33	43
Recorded investment	1,780	1,970
Unpaid principal balance	2,109	2,177
Real Estate Mortgage Portfolio Segment [Member] | Commercial Loans [Member]
Recorded investment, with no related allowance	2,561	1,867
Unpaid principal balance, with no related allowance	2,561	2,186
Recorded investment, with related allowance		7,666
Unpaid principal balance, with related allowance		7,676
Related allowance	670	643
Recorded investment	11,261	9,533
Unpaid principal balance	11,271	9,862
Consumer Portfolio Segment [Member]
Recorded investment, with no related allowance		2
Unpaid principal balance, with no related allowance		2
Recorded investment, with related allowance	1
Unpaid principal balance, with related allowance	1
Related allowance		1
Recorded investment	1	2
Unpaid principal balance	1	$ 2
Real Estate Construction Porfolio Segment [Member] | Residential Loan [Member]
Recorded investment, with related allowance	654
Unpaid principal balance, with related allowance	703
Related allowance	$ 33

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=118936363&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=118936363&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=118936363&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=118936363&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=118936363&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=118936363&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=118936363&loc=d3e5212-111524

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