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Note 8 - Loans and Related Allowance for Loan and Lease Losses (Details Textual) | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Sep. 30, 2021 USD ($) | Sep. 30, 2020 USD ($) | Sep. 30, 2021 USD ($) | Sep. 30, 2020 USD ($) | Dec. 31, 2020 USD ($)
Loans and Leases Receivable, Net of Deferred Income, Total | $ 1,010,282,000 |  | $ 1,010,282,000 |  | $ 1,104,085,000
Loans and Leases Receivable, Deferred Income, Total | 3,700,000 |  | 3,700,000 |  | 4,400,000
Financing Receivable, Troubled Debt Restructuring | 2,600,000 |  | 2,600,000 |  | 2,900,000
Financing Receivable, Allowance for Credit Loss, Writeoff |  |  | $ 108,000 |  | 45,000
Number of Days Past Due (Day) |  |  | 90 days |  |
Loans and Leases Receivable, Impaired, Interest Lost on Nonaccrual Loans | 107,000 | $ 112,000 | $ 290,000 | $ 215,000 |
Provision for Loan and Lease Losses, Total | 0 | 4,000,000 | 900,000 | 7,740,000 |
Allowance for Loan and Lease Losses, Write-offs | 50,000 | 3,043,000 | 442,000 | 3,758,000 |
Other Real Estate, Ending Balance | $ 7,090,000 | $ 7,000,000.0 | $ 7,090,000 | $ 7,000,000.0 | 7,387,000
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts | 0 | 0 | 0 | 0 |
Financing Receivable, Modifications, Number of Contracts | 0 |  | 0 |  |
Threshold For Loans Evaluated For Impairment [Member] |  |  |  |  |
Loans and Leases Receivable, before Fees, Gross | $ 750,000 |  | $ 750,000 |  |
Threshold For Loans Evaluated For Impairment [Member] | Outside Consultant [Member] |  |  |  |  |
Loans and Leases Receivable, before Fees, Gross | 250,000 |  | 250,000 |  |
Threshold For Loans Evaluated For Impairment [Member] | Criticized Relationships [Member] |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss, Total | 150,000 |  | 150,000 |  |
Provision Fluctuation [Member] |  |  |  |  |
Provision for Loan and Lease Losses, Total |  |  |  | $ 2,200,000 |
Non-owner occupied Loan [Member] |  |  |  |  |
Provision for Loan and Lease Losses, Total |  |  |  | 1,300,000 |
Commercial And Industrial [Member] |  |  |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 163,052,000 |  | 163,052,000 |  | 232,044,000
Provision for Loan and Lease Losses, Total | 17,000 | $ 385,000 | (264,000) | 964,000 |
Allowance for Loan and Lease Losses, Write-offs | (0) | $ 16,000 | (0) | $ 185,000 |
Financing Receivable, Modifications, Number of Contracts |  | 1 |  | 3 |
Commercial Real Estate Portfolio Segment [Member] | Provision Fluctuation [Member] |  |  |  |  |
Allowance for Loan and Lease Losses, Write-offs |  | $ 3,000,000.0 |  |  |
Commercial Real Estate Portfolio Segment [Member] | Non-owner occupied Loan [Member] |  |  |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 310,222,000 |  | 310,222,000 |  | 309,424,000
Provision for Loan and Lease Losses, Total | 126,000 | 3,267,000 | 1,196,000 | $ 4,972,000 |
Allowance for Loan and Lease Losses, Write-offs | 50,000 | 3,021,000 | 313,000 | 3,022,000 |
Small Business Administration (SBA), CARES Act, Paycheck Protection Program [Member] |  |  |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 54,200,000 |  | 54,200,000 |  |
Loans and Leases Receivable, Deferred Income, Total | 2,100,000 |  | 2,100,000 |  | 2,700,000
Small Business Administration (SBA), CARES Act, Paycheck Protection Program [Member] | Commercial And Industrial [Member] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss, Ending Balance |  | $ 423,000 |  | $ 423,000 |
Small Business Administration (SBA), CARES Act, Paycheck Protection Program [Member] | Commercial And Industrial [Member] |  |  |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | $ 54,200,000 |  | $ 54,200,000 |  | $ 116,100,000
Financing Receivable, Allowance for Credit Losses, Percentage of Portfolio | 0.40% |  | 0.40% |  |
Financing Receivable, Allowance for Credit Loss, Ending Balance | $ 216,000 |  | $ 216,000 |  |

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- Definition Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(3) -URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953423-111524 + Details
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