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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 | 6 Months Ended
--- | --- | ---
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018
Average recorded investment | $ 15,650 | $ 13,659 | $ 15,125 | $ 13,385
Interest income recognized | 123 | 87 | 244 | 176
Commercial And Industrial [Member] |  |  |  |
Average recorded investment | 1,970 | 4,277 | 2,170 | 3,644
Interest income recognized | 23 | 23 | 45 | 47
Real Estate Construction Porfolio Segment [Member] |  |  |  |
Average recorded investment | 1,620 | 142 | 1,080 | 283
Interest income recognized |  |  |  |
Real Estate Mortgage Portfolio Segment [Member] | Residential Loan [Member] |  |  |  |
Average recorded investment | 1,820 | 2,772 | 1,870 | 2,871
Interest income recognized | 15 | 13 | 27 | 27
Real Estate Mortgage Portfolio Segment [Member] | Commercial Loans [Member] |  |  |  |
Average recorded investment | 10,238 | 6,464 | 10,003 | 6,583
Interest income recognized | 85 | 51 | 172 | 102
Consumer Portfolio Segment [Member] |  |  |  |
Average recorded investment | 2 | 4 | 2 | 4
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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