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Note 3 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans (Details Textual) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2021 USD ($) | Mar. 31, 2020 USD ($) | Dec. 31, 2020 USD ($)
Ratio of Allowance for Loan Losses to End of Period Loans, Excluding PPP Loans |  | 1.16% |  |  | 1.16%
Interest and Fee Income, Loans and Leases, Total |  | $ 8,550 |  | $ 8,466 |
Threshold Period for Considering Loans as Special Mention or Classified (Day) |  | 75 days |  |  |
Financing Receivable, Troubled Debt Restructuring |  | $ 4,285 |  | $ 4,783 | $ 4,249
Financing Receivable, Modifications, Number of Contracts |  | 1 |  | 0 |
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts |  | 0 |  | 0 |
Special Mention [Member] |  |  |  |  |
Increase in Percentage of Allocation Loans Rated Special Mention |  | 50.00% |  |  |
Classified Excluding Impaired [Member] |  |  |  |  |
Increase in Percentage of Allocation Loans Rated Classified |  | 100.00% |  |  |
Financing Receivables 30 to 89 Days Past Due [Member] |  |  |  |  |
Financing Receivable, Past Due | [1] | $ 1,804 |  |  | 1,497
Commercial Non Real Estate Segment [Member] | Commercial and Industrial [Member] | Financing Receivables 30 to 89 Days Past Due [Member] |  |  |  |  |
Financing Receivable, Past Due | [1] | 874 | [2] |  | 730
Commercial Non Real Estate Segment [Member] | Commercial and Industrial [Member] | SBA CARES Act Paycheck Protection Program [Member] | Financing Receivables 30 to 89 Days Past Due [Member] |  |  |  |  |
Financing Receivable, Past Due |  | 3 |  |  |
Nonperforming Financial Instruments [Member] |  |  |  |  |
Interest and Fee Income, Loans and Leases, Total |  | $ 0 |  | $ 0 | $ 0
[1] | Only classes with past due or nonaccrual loans are shown.
[2] | Includes SBA PPP loans past due 30-89 days of $3

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- Definition The aggregate interest and fee income generated by: (1) loans the Entity has positive intent and ability to hold for the foreseeable future, or until maturity or payoff, including commercial and consumer loans, whether domestic or foreign, which may consist of: (a) industrial and agricultural; (b) real estate; and (c) real estate construction loans; (d) trade financing; (e) lease financing; (f) home equity lines-of-credit; (g) automobile and other vehicle loans; and (h) credit card and other revolving-type loans and (2) loans and leases held-for-sale which may include mortgage loans, direct financing, and sales-type leases. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.1) -URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260 + Details
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