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Note 5 - Loans and Related Allowance for Loan and Lease Losses - Additional Information on Impaired Loans (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018
Average recorded investment | $ 14,589 | $ 13,558
Interest income recognized | 567 | 606
Commercial And Industrial [Member] |  |
Average recorded investment | 1,770 | 4,210
Interest income recognized | 141 | 172
Real Estate Construction Porfolio Segment [Member] |  |
Average recorded investment | 648 | 9
Interest income recognized |  |
Real Estate Mortgage Portfolio Segment [Member] | Residential Loan [Member] |  |
Average recorded investment | 1,803 | 2,531
Interest income recognized | 51 | 57
Real Estate Mortgage Portfolio Segment [Member] | Commercial Loans [Member] |  |
Average recorded investment | 10,366 | 6,805
Interest income recognized | 375 | 377
Consumer Portfolio Segment [Member] |  |
Average recorded investment | 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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