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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
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Dec. 31, 2021 | Dec. 31, 2020
Average recorded investment | $ 8,573 | $ 14,297
Interest income recognized | 445 | 358
Commercial Real Estate Portfolio Segment [Member] | Owner Occupied Loan [Member] |  |
Average recorded investment | 1,334 | 2,851
Interest income recognized | 53 | 72
Commercial Real Estate Portfolio Segment [Member] | Non-owner occupied Loan [Member] |  |
Average recorded investment | 5,023 | 8,815
Interest income recognized | 262 | 184
Residential Portfolio Segment [Member] |  |
Average recorded investment | 1,208 | 1,247
Interest income recognized | 56 | 52
Commercial And Industrial [Member] |  |
Average recorded investment | 763 | 1,076
Interest income recognized | 62 | 42
Home Equity Lines of Credit [Member] |  |
Average recorded investment | 245 | 308
Interest income recognized | $ 12 | $ 8

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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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- 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=123577603&loc=d3e5212-111524 + Details
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