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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, 2018 | Dec. 31, 2017
--- | --- | ---
Recorded investment, with no related allowance | $ 4,202 | $ 4,053
Unpaid principal balance, with no related allowance | 4,762 | 4,942
Recorded investment, with related allowance | 14,018 | 8,056
Unpaid principal balance, with related allowance | 14,948 | 8,980
Related allowance | 1,877 | 1,567
Recorded investment | 18,220 | 12,109
Unpaid principal balance | 19,710 | 13,922
Commercial Loans [Member] |  |
Recorded investment, with related allowance | 4,988 |
Unpaid principal balance, with related allowance | 5,169 |
Related allowance | 756 |
Commercial And Industrial [Member] |  |
Recorded investment, with no related allowance | 976 | 450
Unpaid principal balance, with no related allowance | 1,173 | 1,006
Recorded investment, with related allowance | 7,908 | 3,177
Unpaid principal balance, with related allowance | 8,611 | 3,888
Related allowance | 997 | 694
Recorded investment | 8,884 | 3,627
Unpaid principal balance | 9,784 | 4,894
Real Estate Construction Porfolio Segment [Member] |  |
Recorded investment, with no related allowance |  | 44
Unpaid principal balance, with no related allowance |  | 44
Related allowance |  |
Recorded investment |  | 44
Unpaid principal balance |  | 44
Real Estate Construction Porfolio Segment [Member] | Residential Loan [Member] |  |
Recorded investment, with related allowance | 1,119 |
Unpaid principal balance, with related allowance | 1,165 |
Related allowance | 124 |
Real Estate Mortgage Portfolio Segment [Member] | Residential Loan [Member] |  |
Recorded investment, with no related allowance | 1,597 | 1,685
Unpaid principal balance, with no related allowance | 1,822 | 1,904
Recorded investment, with related allowance |  | 1,139
Unpaid principal balance, with related allowance |  | 1,179
Related allowance | 124 | 140
Recorded investment | 2,716 | 2,824
Unpaid principal balance | 2,987 | 3,083
Real Estate Mortgage Portfolio Segment [Member] | Commercial Loans [Member] |  |
Recorded investment, with no related allowance | 1,629 | 1,870
Unpaid principal balance, with no related allowance | 1,767 | 1,984
Recorded investment, with related allowance |  | 3,740
Unpaid principal balance, with related allowance |  | 3,913
Related allowance | 756 | 733
Recorded investment | 6,617 | 5,610
Unpaid principal balance | 6,936 | 5,897
Consumer Portfolio Segment [Member] |  |
Recorded investment, with no related allowance |  | 4
Unpaid principal balance, with no related allowance |  | 4
Recorded investment, with related allowance | 3 |
Unpaid principal balance, with related allowance | 3 |
Related allowance |  |
Recorded investment | 3 | 4
Unpaid principal balance | $ 3 | $ 4

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- 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=84173941&loc=SL6953550-111524 + Details
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- 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=84173941&loc=d3e5212-111524 + Details
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- 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=84173941&loc=d3e5212-111524 + Details
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