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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, 2018 | Jun. 30, 2017 | Jun. 30, 2018 | Jun. 30, 2017
Average recorded investment | $ 13,659 | $ 14,683 | $ 13,385 | $ 14,258
Interest income recognized | 87 | 181 | 176 | 375
Commercial And Industrial [Member] |  |  |  |
Average recorded investment | 4,277 | 2,228 | 3,644 | 1,889
Interest income recognized | 23 | 57 | 47 | 141
Real Estate Construction Porfolio Segment [Member] |  |  |  |
Average recorded investment | 142 | 676 | 283 | 877
Interest income recognized |  | 1 |  | 1
Real Estate Mortgage Portfolio Segment [Member] | Residential Loan [Member] |  |  |  |
Average recorded investment | 2,772 | 3,131 | 2,871 | 3,264
Interest income recognized | 13 | 28 | 27 | 50
Real Estate Mortgage Portfolio Segment [Member] | Commercial Loans [Member] |  |  |  |
Average recorded investment | 6,464 | 8,643 | 6,583 | 8,223
Interest income recognized | 51 | 95 | 102 | 183
Consumer Portfolio Segment [Member] |  |  |  |
Average recorded investment | 4 | 5 | 4 | 5
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=84173941&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=84173941&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=84173941&loc=d3e5212-111524 + Details
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