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Note 5 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans - Past Due and Nonaccrual Loans (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Nonaccruals |  | $ 3,685 | [1] | $ 3,375 | [2]
Loans past due 90 days or more and still accruing |  | 17 | [1] | 231 | [2]
Consumer Real Estate Portfolio Segment [Member] | Closed End First Liens [Member] |  |  |  |  |
Nonaccruals |  | 62 | [1] | 22 | [2]
Loans past due 90 days or more and still accruing | [2] |  |  | 188 |
Consumer Real Estate Portfolio Segment [Member] | Investor Owned Residential Real Estate [Member] |  |  |  |  |
Nonaccruals | [2] |  |  | 264 |
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate, Owner Occupied [Member] |  |  |  |  |
Nonaccruals |  | 2,941 | [1] | 514 | [2]
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Other [Member] |  |  |  |  |
Nonaccruals |  | 654 | [1] | 2,435 | [2]
Commercial Non Real Estate Segment [Member] | Commercial and Industrial [Member] |  |  |  |  |
Nonaccruals |  | 28 | [1] | 136 | [2]
Loans past due 90 days or more and still accruing | [2] |  |  | 17 |
Consumer Non Real Estate Portfolio Segment [Member] | Credit Card Receivable [Member] |  |  |  |  |
Loans past due 90 days or more and still accruing | [1] | 3 |  |  |
Consumer Non Real Estate Portfolio Segment [Member] | Automobile Loan [Member] |  |  |  |  |
Nonaccruals | [2] |  |  | 4 |
Loans past due 90 days or more and still accruing |  | 1 | [1] | 14 | [2]
Consumer Non Real Estate Portfolio Segment [Member] | Other Consumer Loans [Member] |  |  |  |  |
Loans past due 90 days or more and still accruing |  | 13 | [1] | 12 | [2]
Financing Receivables 30 to 89 Days Past Due [Member] |  |  |  |  |
Loans past due and accruing |  | 1,497 | [1] | 1,070 | [2]
Financing Receivables 30 to 89 Days Past Due [Member] | Consumer Real Estate Portfolio Segment [Member] | Closed End First Liens [Member] |  |  |  |  |
Loans past due and accruing |  | 365 | [1] | 499 | [2]
Financing Receivables 30 to 89 Days Past Due [Member] | Consumer Real Estate Portfolio Segment [Member] | Investor Owned Residential Real Estate [Member] |  |  |  |  |
Loans past due and accruing | [1] | 106 |  |  |
Financing Receivables 30 to 89 Days Past Due [Member] | Consumer Real Estate Portfolio Segment [Member] | Closed End Junior Liens [Member] |  |  |  |  |
Loans past due and accruing | [2] |  |  | 83 |
Financing Receivables 30 to 89 Days Past Due [Member] | Real Estate Construction Portfolio Segment[Member] | Construction, Other [Member] |  |  |  |  |
Loans past due and accruing | [1] |  |  | 19 |
Financing Receivables 30 to 89 Days Past Due [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate, Owner Occupied [Member] |  |  |  |  |
Loans past due and accruing | [1] | 15 |  |  |
Financing Receivables 30 to 89 Days Past Due [Member] | Commercial Real Estate Portfolio Segment [Member] | Multifamily Real Estate [Member] |  |  |  |  |
Loans past due and accruing | [2] |  |  | 94 |
Financing Receivables 30 to 89 Days Past Due [Member] | Commercial Non Real Estate Segment [Member] | Commercial and Industrial [Member] |  |  |  |  |
Loans past due and accruing |  | 730 | [1] | 45 | [2]
Financing Receivables 30 to 89 Days Past Due [Member] | Consumer Non Real Estate Portfolio Segment [Member] | Credit Card Receivable [Member] |  |  |  |  |
Loans past due and accruing |  | 7 | [1] | 4 | [2]
Financing Receivables 30 to 89 Days Past Due [Member] | Consumer Non Real Estate Portfolio Segment [Member] | Automobile Loan [Member] |  |  |  |  |
Loans past due and accruing |  | 144 | [1] | 256 | [2]
Financing Receivables 30 to 89 Days Past Due [Member] | Consumer Non Real Estate Portfolio Segment [Member] | Other Consumer Loans [Member] |  |  |  |  |
Loans past due and accruing |  | 130 | [1] | 70 | [2]
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] |  |  |  |  |
Loans past due and accruing |  | 1,331 | [1] | 940 | [2]
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Consumer Real Estate Portfolio Segment [Member] | Closed End First Liens [Member] |  |  |  |  |
Loans past due and accruing |  | 62 | [1] | 210 | [2]
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Consumer Real Estate Portfolio Segment [Member] | Investor Owned Residential Real Estate [Member] |  |  |  |  |
Loans past due and accruing | [2] |  |  | 264 |
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate, Owner Occupied [Member] |  |  |  |  |
Loans past due and accruing |  | 571 | [1] | 287 | [2]
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Other [Member] |  |  |  |  |
Loans past due and accruing | [1] | 654 |  |  |
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Non Real Estate Segment [Member] | Commercial and Industrial [Member] |  |  |  |  |
Loans past due and accruing |  | 27 | [1] | 153 | [2]
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Consumer Non Real Estate Portfolio Segment [Member] | Credit Card Receivable [Member] |  |  |  |  |
Loans past due and accruing | [1] | 3 |  |  |
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Consumer Non Real Estate Portfolio Segment [Member] | Automobile Loan [Member] |  |  |  |  |
Loans past due and accruing |  | 1 | [1] | 14 | [2]
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Consumer Non Real Estate Portfolio Segment [Member] | Other Consumer Loans [Member] |  |  |  |  |
Loans past due and accruing |  | $ 13 | [1] | $ 12 | [2]
[1] | Only classes with past due or nonaccrual loans are presented
[2] | Only classes with past-due or nonaccrual loans are shown.

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