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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, 2021 | Dec. 31, 2020
--- | --- | ---
Principal balance |  | $ 6,478 | $ 5,453
Total recorded investment | [1] | 5,878 | 4,903
Recorded investment for which there is a related allowance | [1] | 0 | 1,045
Related allowance |  | (0) | 75
Recorded investment for which there is no related allowance | [1] | 5,878 | 3,858
Consumer Real Estate Portfolio Segment [Member] | Investor Owned Residential Real Estate [Member] |  |  |
Principal balance | [2] | 191 | 194
Total recorded investment | [1],[2] | 191 | 194
Recorded investment for which there is a related allowance | [1],[2] | 0 | 194
Related allowance | [2] | 0 | 2
Recorded investment for which there is no related allowance | [1],[2] |  | 0
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate, Owner Occupied [Member] |  |  |
Principal balance | [2] | 3,256 | 3,752
Total recorded investment | [1],[2] | 2,665 | 3,202
Recorded investment for which there is no related allowance | [1],[2] | 2,665 | 3,202
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Other [Member] |  |  |
Principal balance | [2] | 2,721 | 654
Total recorded investment | [1],[2] | 2,721 | 654
Recorded investment for which there is no related allowance | [1],[2] | 2,721 | 654
Commercial Non Real Estate Segment [Member] | Commercial and Industrial [Member] |  |  |
Principal balance | [2] | 310 | 851
Total recorded investment | [1],[2] | 301 | 851
Recorded investment for which there is a related allowance | [1],[2] | 0 | 851
Related allowance | [2] | $ 0 | 73
Consumer Non Real Estate Portfolio Segment [Member] | Automobile Loan [Member] |  |  |
Principal balance | [2] |  | 2
Total recorded investment | [1],[2] |  | 2
Recorded investment for which there is no related allowance | [1],[2] |  | $ 2
[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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- 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 http://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 http://asc.fasb.org/extlink&oid=123577603&loc=d3e5212-111524 + Details
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