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Note 8 - Loans and Related Allowance for Loan and Lease Losses - Impaired Loans by Class (Details) - USD ($) $ in Thousands | Mar. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Recorded investment, with no related allowance | $ 6,129 | $ 7,344
Unpaid principal balance, with no related allowance | 6,923 | 8,199
Recorded investment, with related allowance | 6,757 | 5,726
Unpaid principal balance, with related allowance | 6,818 | 5,787
Related allowance | 1,216 | 660
Recorded investment | 12,886 | 13,070
Unpaid principal balance | 13,741 | 13,986
Commercial Real Estate Portfolio Segment [Member] | Owner Occupied Loan [Member] |  |
Recorded investment, with no related allowance | 1,749 | 1,772
Unpaid principal balance, with no related allowance | 1,749 | 1,772
Recorded investment, with related allowance | 1,683 | 1,702
Unpaid principal balance, with related allowance | 1,693 | 1,713
Related allowance | 53 | 45
Recorded investment | 3,432 | 3,474
Unpaid principal balance | 3,442 | 3,485
Commercial Real Estate Portfolio Segment [Member] | Non-owner occupied Loan [Member] |  |
Recorded investment, with no related allowance | 2,773 | 3,845
Unpaid principal balance, with no related allowance | 2,773 | 3,845
Recorded investment, with related allowance | 4,270 | 3,239
Unpaid principal balance, with related allowance | 4,270 | 3,239
Related allowance | 1,095 | 582
Recorded investment | 7,043 | 7,084
Unpaid principal balance | 7,043 | 7,084
Residential Portfolio Segment [Member] |  |
Recorded investment, with no related allowance | 636 | 759
Unpaid principal balance, with no related allowance | 699 | 829
Recorded investment, with related allowance | 516 | 519
Unpaid principal balance, with related allowance | 567 | 569
Related allowance | 25 | 28
Recorded investment | 1,152 | 1,278
Unpaid principal balance | 1,266 | 1,398
Commercial And Industrial [Member] |  |
Recorded investment, with no related allowance | 791 | 747
Unpaid principal balance, with no related allowance | 1,512 | 1,524
Recorded investment, with related allowance | 120 | 135
Unpaid principal balance, with related allowance | 120 | 135
Related allowance | 3 | 3
Recorded investment | 911 | 882
Unpaid principal balance | 1,632 | 1,659
Home Equity Lines of Credit [Member] |  |
Recorded investment, with no related allowance | 179 | 220
Unpaid principal balance, with no related allowance | 189 | 228
Recorded investment, with related allowance | 168 | 131
Unpaid principal balance, with related allowance | 168 | 131
Related allowance | 40 | 2
Recorded investment | 347 | 351
Unpaid principal balance | 357 | 359
Consumer Portfolio Segment [Member] |  |
Recorded investment, with no related allowance | 1 | 1
Unpaid principal balance, with no related allowance | 1 | 1
Related allowance |  |
Recorded investment | 1 | 1
Unpaid principal balance | $ 1 | $ 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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