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Note 5 - Loans and Related Allowance for Loan and Lease Losses (Details Textual) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2021 USD ($) | Sep. 30, 2021 USD ($) | Jun. 30, 2021 USD ($) | Mar. 31, 2021 USD ($) | Dec. 31, 2020 USD ($) | Sep. 30, 2020 USD ($) | Jun. 30, 2020 USD ($) | Mar. 31, 2020 USD ($) | Dec. 31, 2021 USD ($) | Dec. 31, 2020 USD ($)
Loans and Leases Receivable, Net of Deferred Income, Total | $ 981,691,000 |  |  |  | $ 1,104,085,000 |  |  |  | $ 981,691,000 | $ 1,104,085,000
Loans and Leases Receivable, Deferred Income, Total | 3,600,000 |  |  |  | 4,400,000 |  |  |  | 3,600,000 | 4,400,000
Financing Receivable, Troubled Debt Restructuring | $ 2,600,000 |  |  |  | $ 2,900,000 |  |  |  | 2,600,000 | 2,900,000
Financing Receivable, Allowance for Credit Loss, Writeoff |  |  |  |  |  |  |  |  | $ 150,000 | $ 45,000
Financing Receivable, Number of Payment Modifications | 0 |  |  |  | 11 |  |  |  | 0 | 11
Financing Receivable, Loans Modified, Outstanding Amount |  |  |  |  | $ 24,500,000 |  |  |  |  | $ 24,500,000
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts |  |  |  |  |  |  |  |  | 0 | 0
Number of Days Past Due (Day) |  |  |  |  |  |  |  |  | 90 days |
Financing Receivable, 90 Days or More Past Due, Still Accruing | $ 0 |  |  |  | 0 |  |  |  | $ 0 | $ 0
Allowance for Loan and Lease Losses, Write-offs |  |  |  |  |  |  |  |  | 465,000 | 3,839,000
Provision for Loan and Lease Losses, Total | (200,000) | $ 0 | $ 200,000 | $ 700,000 | 2,100,000 | $ 4,000,000 | $ 1,000,000 | $ 2,740,000 | 700,000 | 9,840,000
Threshold For Loans Evaluated For Impairment [Member] |  |  |  |  |  |  |  |  |  |
Loans and Leases Receivable, before Fees, Gross | 750,000 |  |  |  |  |  |  |  | 750,000 |
Commercial And Industrial [Member] |  |  |  |  |  |  |  |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 148,812,000 |  |  |  | 232,044,000 |  |  |  | 148,812,000 | 232,044,000
Financing Receivable, 90 Days or More Past Due, Still Accruing | 0 |  |  |  | 0 |  |  |  | 0 | 0
Allowance for Loan and Lease Losses, Write-offs |  |  |  |  |  |  |  |  | 1,000 | 245,000
Provision for Loan and Lease Losses, Total |  |  |  |  |  |  |  |  | (664,000) | 848,000
Commercial And Industrial [Member] | Provision Fluctuation [Member] |  |  |  |  |  |  |  |  |  |
Allowance for Loan and Lease Losses, Write-offs |  |  |  |  |  |  |  |  |  | 245,000
Commercial Real Estate Portfolio Segment [Member] | Provision Fluctuation [Member] |  |  |  |  |  |  |  |  |  |
Allowance for Loan and Lease Losses, Write-offs |  |  |  |  |  |  |  |  |  | 3,000,000.0
Residential Portfolio Segment [Member] |  |  |  |  |  |  |  |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 240,089,000 |  |  |  | 233,995,000 |  |  |  | 240,089,000 | 233,995,000
Financing Receivable, 90 Days or More Past Due, Still Accruing | 0 |  |  |  | 0 |  |  |  | 0 | 0
Allowance for Loan and Lease Losses, Write-offs |  |  |  |  |  |  |  |  | 27,000 | 62,000
Provision for Loan and Lease Losses, Total |  |  |  |  |  |  |  |  | 57,000 | 977,000
Residential Portfolio Segment [Member] | Provision Fluctuation [Member] |  |  |  |  |  |  |  |  |  |
Allowance for Loan and Lease Losses, Write-offs |  |  |  |  |  |  |  |  |  | 62,000
Consumer Portfolio Segment [Member] |  |  |  |  |  |  |  |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | 8,010,000 |  |  |  | 9,823,000 |  |  |  | 8,010,000 | 9,823,000
Financing Receivable, 90 Days or More Past Due, Still Accruing | 0 |  |  |  | 0 |  |  |  | 0 | 0
Allowance for Loan and Lease Losses, Write-offs |  |  |  |  |  |  |  |  | 124,000 | 405,000
Provision for Loan and Lease Losses, Total |  |  |  |  |  |  |  |  | (24,000) | 375,000
Consumer Portfolio Segment [Member] | Provision Fluctuation [Member] |  |  |  |  |  |  |  |  |  |
Allowance for Loan and Lease Losses, Write-offs |  |  |  |  |  |  |  |  |  | 383,000
Small Business Administration (SBA), CARES Act, Paycheck Protection Program [Member] |  |  |  |  |  |  |  |  |  |
Loans and Leases Receivable, Deferred Income, Total | 1,300,000 |  |  |  | 2,700,000 |  |  |  | 1,300,000 | 2,700,000
Small Business Administration (SBA), CARES Act, Paycheck Protection Program [Member] | Commercial And Industrial [Member] |  |  |  |  |  |  |  |  |  |
Loans and Leases Receivable, Net of Deferred Income, Total | $ 34,100,000 |  |  |  | $ 116,100,000 |  |  |  | $ 34,100,000 | $ 116,100,000
Financing Receivable, Allowance for Credit Losses, Percentage of Portfolio | 0.40% |  |  |  | 0.40% |  |  |  | 0.40% | 0.40%
Financing Receivable, Allowance for Credit Loss, Ending Balance | $ 137,000 |  |  |  | $ 464,000 |  |  |  | $ 137,000 | $ 464,000
Provision for Loan and Lease Losses, Total |  |  |  |  |  |  |  |  |  | $ 464,000

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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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