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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, 2022 | Dec. 31, 2021
--- | --- | ---
Principal balance | [1] | $ 3,719 | $ 6,478
Total recorded investment | [1],[2] | 3,032 | 5,878
Recorded investment for which there is no related allowance | [1] | 3,032 | 5,878
Recorded investment for which there is a related allowance | [1] | 0 | 0
Related allowance | [1] | (0) | (0)
Consumer Real Estate Portfolio Segment [Member] | Investor Owned Residential Real Estate [Member] |  |  |
Principal balance | [1] | 186 | 191
Total recorded investment | [1],[2] | 186 | 191
Recorded investment for which there is no related allowance | [1] | 186 | 191
Recorded investment for which there is a related allowance | [1] | 0 | 0
Related allowance | [1] | 0 | 0
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate, Owner Occupied [Member] |  |  |
Principal balance | [1] | 3,248 | 3,256
Total recorded investment | [1],[2] | 2,583 | 2,665
Recorded investment for which there is no related allowance | [1] | 2,583 | 2,665
Recorded investment for which there is a related allowance | [1] | 0 | 0
Related allowance | [1] | 0 | 0
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Other [Member] |  |  |
Principal balance | [1] |  | 2,721
Total recorded investment | [1],[2] |  | 2,721
Recorded investment for which there is no related allowance | [1] |  | 2,721
Recorded investment for which there is a related allowance | [1] |  | 0
Related allowance | [1] |  | 0
Commercial Non Real Estate Segment [Member] | Commercial and Industrial [Member] |  |  |
Principal balance | [1] | 285 | 310
Total recorded investment | [1],[2] | 263 | 301
Recorded investment for which there is no related allowance | [1] | 263 | 301
Recorded investment for which there is a related allowance | [1] | 0 | 0
Related allowance | [1] | $ 0 | $ 0
[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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- 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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- Definition Amount of allowance for credit losses related to recorded investment. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (a)(3) -URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5212-111524 + Details
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