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Note 8 - Loans and Related Allowance for Loan and Lease Losses - Impaired Loans by Class (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Recorded investment, with no related allowance	$ 4,790	$ 3,380
Unpaid principal balance, with no related allowance	5,718	4,061
Recorded investment, with related allowance	11,181	10,695
Unpaid principal balance, with related allowance	11,461	11,406
Related allowance	963	1,354
Recorded investment	15,971	14,075
Unpaid principal balance	17,179	15,467
Commercial Loans [Member]
Recorded investment, with related allowance	6,428
Unpaid principal balance, with related allowance	6,446
Related allowance	54
Commercial And Industrial [Member]
Recorded investment, with no related allowance	671	207
Unpaid principal balance, with no related allowance	1,169	413
Recorded investment, with related allowance	1,154	2,363
Unpaid principal balance, with related allowance	1,365	3,013
Related allowance	203	667
Recorded investment	1,825	2,570
Unpaid principal balance	2,534	3,426
Real Estate Mortgage Portfolio Segment [Member] | Residential Loan [Member]
Recorded investment, with no related allowance	1,496	1,306
Unpaid principal balance, with no related allowance	1,660	1,462
Recorded investment, with related allowance		664
Unpaid principal balance, with related allowance		715
Related allowance	45	43
Recorded investment	1,856	1,970
Unpaid principal balance	2,071	2,177
Real Estate Mortgage Portfolio Segment [Member] | Commercial Loans [Member]
Recorded investment, with no related allowance	2,621	1,867
Unpaid principal balance, with no related allowance	2,887	2,186
Recorded investment, with related allowance		7,666
Unpaid principal balance, with related allowance		7,676
Related allowance	54	643
Recorded investment	9,049	9,533
Unpaid principal balance	9,333	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	2
Unpaid principal balance, with related allowance	2
Related allowance		1
Recorded investment	2	2
Unpaid principal balance	2	$ 2
Real Estate Construction Porfolio Segment [Member]
Recorded investment, with related allowance	3,239
Unpaid principal balance, with related allowance	3,239
Related allowance	661
Recorded investment	3,239
Unpaid principal balance	3,239
Real Estate Construction Porfolio Segment [Member] | Residential Loan [Member]
Recorded investment, with related allowance	360
Unpaid principal balance, with related allowance	411
Related allowance	$ 45

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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X

- Definition

Amount of investment in impaired financing receivables for which there is no 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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- Definition

Amount of unpaid principal balance of impaired financing receivables for which there is no 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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X

- Definition

Amount of investment in impaired financing receivables for which there is 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

Unpaid principal balance of impaired financing receivables for which there is 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 15
-Subparagraph (a)(4)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5212-111524

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