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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, 2022 | Dec. 31, 2021
--- | --- | ---
Principal balance |  | $ 6,462 | $ 6,478 |
Total recorded investment | [1] | 5,834 | 5,878 |
Recorded investment for which there is no related allowance | [1] | 5,834 | 5,878 |
Recorded investment for which there is a related allowance |  | 0 | 0 | [1]
Related allowance |  | 0 | 0 |
Consumer Real Estate Portfolio Segment [Member] | Investor Owned Residential Real Estate [Member] |  |  |  |
Principal balance |  | 189 | 191 |
Total recorded investment | [1] | 189 | 191 |
Recorded investment for which there is no related allowance | [1] | 189 | 191 |
Recorded investment for which there is a related allowance |  | 0 | 0 | [1]
Related allowance |  | 0 | 0 |
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate, Owner Occupied [Member] |  |  |  |
Principal balance |  | 3,254 | 3,256 |
Total recorded investment | [1] | 2,639 | 2,665 |
Recorded investment for which there is no related allowance | [1] | 2,639 | 2,665 |
Recorded investment for which there is a related allowance |  | 0 | 0 | [1]
Related allowance |  | 0 | 0 |
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Other [Member] |  |  |  |
Principal balance |  | 2,719 | 2,721 |
Total recorded investment | [1] | 2,719 | 2,721 |
Recorded investment for which there is no related allowance | [1] | 2,719 | 2,721 |
Recorded investment for which there is a related allowance |  | 0 | 0 | [1]
Related allowance |  | 0 | 0 |
Commercial Non Real Estate Segment [Member] | Commercial and Industrial [Member] |  |  |  |
Principal balance |  | 300 | 310 |
Total recorded investment | [1] | 287 | 301 |
Recorded investment for which there is no related allowance | [1] | 287 | 301 |
Recorded investment for which there is a related allowance |  | 0 | 0 | [1]
Related allowance |  | $ 0 | $ 0 |
[1] | Recorded investment is net of charge-offs and interest paid while a loan is in nonaccrual status.

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- Definition Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 14A -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=123577603&loc=SL6953550-111524 + Details
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