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Note 3 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans - Impaired Loans and Associated Reserves (Details) - USD ($) $ in Thousands | Mar. 31, 2020 | Dec. 31, 2019 | Mar. 31, 2019
--- | --- | --- | ---
Principal balance |  | $ 6,158 |  | $ 5,757 |  |
Total recorded investment |  | 5,671 | [1] | 5,289 | [1] | $ 6,337
Impaired loans with no valuation allowance |  | 4,557 | [1] | 4,174 | [1] | 5,212
Recorded investment for which there is a related allowance |  | 1,114 | [1] | 1,115 | [1] | 1,125
Related allowance |  | 110 |  | 110 |  | 132
Recorded investment for which there is no related allowance |  | 4,557 | [1] | 4,174 | [1] | $ 5,212
Consumer Real Estate Portfolio Segment [Member] | Equity Lines [Member] |  |  |  |  |  |
Principal balance |  | 100 | [2] | 100 |  |
Total recorded investment |  | 100 | [1],[2] | 100 |  |
Impaired loans with no valuation allowance |  | 100 | [1],[2] | 100 |  |
Recorded investment for which there is a related allowance |  |  | [1],[2] |  |  |
Related allowance |  |  | [2] |  |  |
Recorded investment for which there is no related allowance |  | 100 | [1],[2] | 100 |  |
Consumer Real Estate Portfolio Segment [Member] | Closed End First Liens [Member] |  |  |  |  |  |
Principal balance | [2] | 23 |  | 221 |  |
Total recorded investment | [1],[2] | 22 |  | 221 |  |
Impaired loans with no valuation allowance | [1],[2] | 22 |  | 221 |  |
Recorded investment for which there is a related allowance | [1],[2] |  |  |  |  |
Related allowance | [2] |  |  |  |  |
Recorded investment for which there is no related allowance | [1],[2] | 22 |  | 221 |  |
Consumer Real Estate Portfolio Segment [Member] | Investor Owned Residential Real Estate [Member] |  |  |  |  |  |
Principal balance | [2] | 488 |  | 441 |  |
Total recorded investment | [1],[2] | 486 |  | 438 |  |
Impaired loans with no valuation allowance | [1],[2] | 289 |  | 241 |  |
Recorded investment for which there is a related allowance | [1],[2] | 197 |  | 197 |  |
Related allowance | [2] | 2 |  | 2 |  |
Recorded investment for which there is no related allowance | [1],[2] | 289 |  | 241 |  |
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate, Owner Occupied [Member] |  |  |  |  |  |
Principal balance | [2] | 921 |  | 929 |  |
Total recorded investment | [1],[2] | 885 |  | 895 |  |
Impaired loans with no valuation allowance | [1],[2] | 885 |  | 895 |  |
Recorded investment for which there is a related allowance | [1],[2] |  |  |  |  |
Related allowance | [2] |  |  |  |  |
Recorded investment for which there is no related allowance | [1],[2] | 885 |  | 895 |  |
Commercial Real Estate Portfolio Segment [Member] | Multifamily Real Estate [Member] |  |  |  |  |  |
Principal balance | [2] |  |  | 278 |  |
Total recorded investment | [1],[2] |  |  | 278 |  |
Impaired loans with no valuation allowance | [1],[2] |  |  | 278 |  |
Recorded investment for which there is a related allowance | [1],[2] |  |  | 0 |  |
Related allowance | [2] |  |  | 0 |  |
Recorded investment for which there is no related allowance | [1],[2] |  |  | 278 |  |
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Other [Member] |  |  |  |  |  |
Principal balance | [2] | 3,705 |  | 2,867 |  |
Total recorded investment | [1],[2] | 3,257 |  | 2,435 |  |
Impaired loans with no valuation allowance | [1],[2] | 3,257 |  | 2,435 |  |
Recorded investment for which there is a related allowance | [1],[2] | 0 |  | 0 |  |
Related allowance | [2] | 0 |  | 0 |  |
Recorded investment for which there is no related allowance | [1],[2] | 3,257 |  | 2,435 |  |
Commercial Non Real Estate Segment [Member] | Commercial and Industrial [Member] |  |  |  |  |  |
Principal balance | [2] | 917 |  | 917 |  |
Total recorded investment | [1],[2] | 917 |  | 918 |  |
Impaired loans with no valuation allowance | [1],[2] |  |  |  |  |
Recorded investment for which there is a related allowance | [1],[2] | 917 |  | 918 |  |
Related allowance | [2] | 108 |  | 108 |  |
Recorded investment for which there is no related allowance | [1],[2] |  |  |  |  |
Consumer Non Real Estate Portfolio Segment [Member] | Automobile Loan [Member] |  |  |  |  |  |
Principal balance | [2] | 4 |  | 4 |  |
Total recorded investment | [1],[2] | 4 |  | 4 |  |
Impaired loans with no valuation allowance | [1],[2] | 4 |  | 4 |  |
Recorded investment for which there is a related allowance | [1],[2] |  |  |  |  |
Related allowance | [2] | 0 |  |  |  |
Recorded investment for which there is no related allowance | [1],[2] | $ 4 |  | $ 4 |  |
[1] | Recorded investment is net of charge-offs and interest paid while a loan is in nonaccrual status.
[2] | Only classes with impaired loans are shown.

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