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Note 5 - Loans and Related Allowance for Loan and Lease Losses - Impaired Loans by Class (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Recorded investment, with no related allowance | $ 3,501 | $ 7,344
Unpaid principal balance, with no related allowance | 4,104 | 8,199
Recorded investment, with related allowance | 4,586 | 5,726
Unpaid principal balance, with related allowance | 4,863 | 5,787
Related allowance | 490 | 660
Recorded investment | 8,087 | 13,070
Unpaid principal balance | 8,967 | 13,986
Commercial Real Estate Portfolio Segment [Member] | Owner Occupied Loan [Member] |  |
Recorded investment, with no related allowance | 1,118 | 1,772
Unpaid principal balance, with no related allowance | 1,142 | 1,772
Recorded investment, with related allowance | 447 | 1,702
Unpaid principal balance, with related allowance | 447 | 1,713
Related allowance | 10 | 45
Recorded investment | 1,565 | 3,474
Unpaid principal balance | 1,589 | 3,485
Commercial Real Estate Portfolio Segment [Member] | Non-owner occupied Loan [Member] |  |
Recorded investment, with no related allowance | 801 | 3,845
Unpaid principal balance, with no related allowance | 801 | 3,845
Recorded investment, with related allowance | 3,322 | 3,239
Unpaid principal balance, with related allowance | 3,596 | 3,239
Related allowance | 371 | 582
Recorded investment | 4,123 | 7,084
Unpaid principal balance | 4,397 | 7,084
Residential Portfolio Segment [Member] |  |
Recorded investment, with no related allowance | 941 | 759
Unpaid principal balance, with no related allowance | 1,013 | 829
Recorded investment, with related allowance | 378 | 519
Unpaid principal balance, with related allowance | 378 | 569
Related allowance | 20 | 28
Recorded investment | 1,319 | 1,278
Unpaid principal balance | 1,391 | 1,398
Commercial And Industrial [Member] |  |
Recorded investment, with no related allowance | 561 | 747
Unpaid principal balance, with no related allowance | 1,056 | 1,524
Recorded investment, with related allowance | 273 | 135
Unpaid principal balance, with related allowance | 276 | 135
Related allowance | 48 | 3
Recorded investment | 834 | 882
Unpaid principal balance | 1,332 | 1,659
Home Equity Lines of Credit [Member] |  |
Recorded investment, with no related allowance | 80 | 220
Unpaid principal balance, with no related allowance | 92 | 228
Recorded investment, with related allowance | 166 | 131
Unpaid principal balance, with related allowance | 166 | 131
Related allowance | 41 | 2
Recorded investment | 246 | 351
Unpaid principal balance | $ 258 | 359
Consumer Portfolio Segment [Member] |  |
Recorded investment, with no related allowance |  | 1
Unpaid principal balance, with no related allowance |  | 1
Related allowance |  | 0
Recorded investment |  | 1
Unpaid principal balance |  | $ 1

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- Definition 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 14A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953550-111524 + Details
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- Definition Amount of allowance for credit losses related to recorded investment. + 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 (a)(3) -URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5212-111524 + Details
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