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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 | 9 Months Ended
--- | --- | ---
Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020
Average recorded investment | $ 8,976 | $ 18,721 | $ 8,725 | $ 15,850
Interest income recognized | 81 | 172 | 219 | 535
Commercial Real Estate Portfolio Segment [Member] | Owner Occupied Loan [Member] |  |  |  |
Average recorded investment | 1,428 | 2,893 | 1,485 | 3,173
Interest income recognized | 14 | 0 | 45 | 55
Commercial Real Estate Portfolio Segment [Member] | Non-owner occupied Loan [Member] |  |  |  |
Average recorded investment | 5,419 | 12,912 | 4,955 | 9,988
Interest income recognized | 34 | 129 | 101 | 387
Residential Portfolio Segment [Member] |  |  |  |
Average recorded investment | 1,190 | 1,242 | 1,234 | 1,229
Interest income recognized | 18 | 14 | 42 | 39
Commercial And Industrial [Member] |  |  |  |
Average recorded investment | 694 | 1,376 | 807 | 1,136
Interest income recognized | 9 | 28 | 22 | 49
Home Equity Lines of Credit [Member] |  |  |  |
Average recorded investment | 245 | 298 | 244 | 323
Interest income recognized | $ 6 | 1 | $ 9 | 5
Consumer Portfolio Segment [Member] |  |  |  |
Average recorded investment |  | 0 |  | 1
Interest income recognized |  | $ 0 |  | $ 0

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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=123577603&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=123577603&loc=d3e5258-111524 + Details
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