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Note 5 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans - Impaired Loans and Associated Reserves (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Principal balance |  | $ 5,453 |  | $ 5,757
Total recorded investment | [1] | 4,903 |  | 5,289
Recorded investment for which there is a related allowance | [1] | 1,045 |  | 1,115
Related allowance |  | 75 |  | 110
Recorded investment for which there is no related allowance | [1] | 3,858 |  | 4,174
Consumer Real Estate Portfolio Segment [Member] | Investor Owned Residential Real Estate [Member] |  |  |  |
Principal balance | [1] | 194 |  | 441
Total recorded investment | [1] | 194 | [2] | 438
Recorded investment for which there is a related allowance | [1] | 194 | [2] | 197
Related allowance | [1] | 2 |  | 2
Recorded investment for which there is no related allowance | [1] |  |  | 241
Consumer Real Estate Portfolio Segment [Member] | Equity Lines [Member] |  |  |  |
Principal balance |  |  |  | 100
Total recorded investment |  |  |  | 100
Related allowance |  |  |  | 0
Recorded investment for which there is no related allowance |  |  |  | 100
Consumer Real Estate Portfolio Segment [Member] | Closed End First Liens [Member] |  |  |  |
Principal balance | [1] |  |  | 221
Total recorded investment | [1] |  |  | 221
Recorded investment for which there is no related allowance | [1] |  |  | 221
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate, Owner Occupied [Member] |  |  |  |
Principal balance | [1] | 3,752 |  | 929
Total recorded investment | [1] | 3,202 | [2] | 895
Recorded investment for which there is no related allowance | [1] | 3,202 | [2] | 895
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Other [Member] |  |  |  |
Principal balance | [1] | 654 |  | 2,867
Total recorded investment | [1] | 654 | [2] | 2,435
Recorded investment for which there is no related allowance | [1] | 654 | [2] | 2,435
Commercial Real Estate Portfolio Segment [Member] | Multifamily Real Estate [Member] |  |  |  |
Principal balance | [1] |  |  | 278
Total recorded investment | [1] |  |  | 278
Recorded investment for which there is no related allowance | [1] |  |  | 278
Commercial Non Real Estate Segment [Member] | Commercial and Industrial [Member] |  |  |  |
Principal balance | [1] | 851 |  | 917
Total recorded investment | [1] | 851 | [2] | 918
Recorded investment for which there is a related allowance | [1] | 851 | [2] | 918
Related allowance | [1] | 73 |  | 108
Consumer Non Real Estate Portfolio Segment [Member] | Automobile Loan [Member] |  |  |  |
Principal balance | [1] | 2 |  | 4
Total recorded investment | [1] | 2 | [2] | 4
Recorded investment for which there is no related allowance | [1] | $ 2 | [2] | $ 4
[1] | Only classes with impaired loans are shown.
[2] | Recorded investment is net of charge-offs and interest paid while a loan is in nonaccrual status.

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