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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
--- | ---
Mar. 31, 2018 | Mar. 31, 2017
Average recorded investment | $ 15,529 | $ 12,356
Interest income recognized | 344 | 194
Commercial And Industrial [Member] |  |
Average recorded investment | 5,631 | 1,372
Interest income recognized | 187 | 84
Real Estate Construction Porfolio Segment [Member] |  |
Average recorded investment | 283 | 810
Interest income recognized |  |
Real Estate Mortgage Portfolio Segment [Member] | Residential Loan [Member] |  |
Average recorded investment | 2,892 | 3,092
Interest income recognized | 21 | 22
Real Estate Mortgage Portfolio Segment [Member] | Commercial Loans [Member] |  |
Average recorded investment | 6,719 | 7,077
Interest income recognized | 136 | 88
Consumer Portfolio Segment [Member] |  |
Average recorded investment | 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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