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Note 8 - Loans and Related Allowance for Loan and Lease Losses - Additional Information on Impaired Loans (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2019 | Sep. 30, 2018 | Sep. 30, 2019 | Sep. 30, 2018
Average recorded investment | $ 14,914 | $ 11,693 | $ 14,968 | $ 13,429
Interest income recognized | 129 | 100 | 368 | 300
Commercial And Industrial [Member] |  |  |  |
Average recorded investment | 1,786 | 2,984 | 1,992 | 4,620
Interest income recognized | 20 | 32 | 44 | 100
Real Estate Construction Porfolio Segment [Member] |  |  |  |
Average recorded investment |  |  | 810 | 11
Interest income recognized |  |  |  |
Real Estate Mortgage Portfolio Segment [Member] | Residential Loan [Member] |  |  |  |
Average recorded investment | 1,782 | 2,574 | 1,847 | 2,672
Interest income recognized | 14 | 18 | 38 | 49
Real Estate Mortgage Portfolio Segment [Member] | Commercial Loans [Member] |  |  |  |
Average recorded investment | 11,344 | 6,132 | 10,317 | 6,123
Interest income recognized | 95 | 50 | 286 | 151
Consumer Portfolio Segment [Member] |  |  |  |
Average recorded investment | 2 | 3 | 2 | 3
Interest income recognized |  |  |  |

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- Definition Average 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 15 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=118936363&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=118936363&loc=d3e5258-111524 + Details
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- Definition Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired. + 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 (c)(2) -URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5212-111524 + Details
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