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Note 8 - Loans and Related Allowance for Loan and Lease Losses - Impaired Loans by Class (Details) - USD ($) $ in Thousands | Sep. 30, 2021 | Dec. 31, 2020
--- | --- | ---
Recorded investment, with no related allowance | $ 3,602 | $ 3,501
Unpaid principal balance, with no related allowance | 4,216 | 4,104
Recorded investment, with related allowance | 6,018 | 4,586
Unpaid principal balance, with related allowance | 6,796 | 4,863
Related allowance | 959 | 490
Recorded investment | 9,620 | 8,087
Unpaid principal balance | 11,012 | 8,967
Commercial Real Estate Portfolio Segment [Member] | Owner Occupied Loan [Member] |  |
Recorded investment, with no related allowance | 981 | 1,118
Unpaid principal balance, with no related allowance | 1,027 | 1,142
Recorded investment, with related allowance | 415 | 447
Unpaid principal balance, with related allowance | 415 | 447
Related allowance | 5 | 10
Recorded investment | 1,396 | 1,565
Unpaid principal balance | 1,442 | 1,589
Commercial Real Estate Portfolio Segment [Member] | Non-owner occupied Loan [Member] |  |
Recorded investment, with no related allowance | 1,624 | 801
Unpaid principal balance, with no related allowance | 1,754 | 801
Recorded investment, with related allowance | 4,520 | 3,322
Unpaid principal balance, with related allowance | 5,194 | 3,596
Related allowance | 739 | 371
Recorded investment | 6,144 | 4,123
Unpaid principal balance | 6,948 | 4,397
Residential Portfolio Segment [Member] |  |
Recorded investment, with no related allowance | 870 | 941
Unpaid principal balance, with no related allowance | 877 | 1,013
Recorded investment, with related allowance | 293 | 378
Unpaid principal balance, with related allowance | 293 | 378
Related allowance | 17 | 20
Recorded investment | 1,163 | 1,319
Unpaid principal balance | 1,170 | 1,391
Commercial And Industrial [Member] |  |
Recorded investment, with no related allowance | 119 | 561
Unpaid principal balance, with no related allowance | 550 | 1,056
Recorded investment, with related allowance | 546 | 273
Unpaid principal balance, with related allowance | 650 | 276
Related allowance | 102 | 48
Recorded investment | 665 | 834
Unpaid principal balance | 1,200 | 1,332
Home Equity Lines of Credit [Member] |  |
Recorded investment, with no related allowance | 8 | 80
Unpaid principal balance, with no related allowance | 8 | 92
Recorded investment, with related allowance | 244 | 166
Unpaid principal balance, with related allowance | 244 | 166
Related allowance | 96 | 41
Recorded investment | 252 | 246
Unpaid principal balance | $ 252 | $ 258

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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=123577603&loc=SL6953550-111524 + Details
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