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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
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Mar. 31, 2020 | Mar. 31, 2019
Average recorded investment | $ 12,979 | $ 15,025
Interest income recognized | 105 | 185
Commercial Real Estate Portfolio Segment [Member] | Owner Occupied Loan [Member] |  |
Average recorded investment | 3,453 | 4,235
Interest income recognized | 33 | 46
Commercial Real Estate Portfolio Segment [Member] | Non-owner occupied Loan [Member] |  |
Average recorded investment | 7,064 | 5,057
Interest income recognized | 49 | 52
Residential Portfolio Segment [Member] |  |
Average recorded investment | 1,215 | 1,795
Interest income recognized | 11 | 11
Commercial And Industrial [Member] |  |
Average recorded investment | 897 | 2,198
Interest income recognized | 10 | 30
Home Equity Lines of Credit [Member] |  |
Average recorded investment | 349 | 118
Interest income recognized | 2 | 1
Construction and Other [Member] |  |
Average recorded investment |  | 1,620
Interest income recognized |  | 45
Consumer Portfolio Segment [Member] |  |
Average recorded investment | 1 | 2
Interest income recognized |  |

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