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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, 2021 | Dec. 31, 2020 | Mar. 31, 2020
--- | --- | --- | ---
Principal balance |  | $ 5,520 |  | $ 5,453 |  |
Total recorded investment |  | 4,939 | [1] | 4,903 | [1] | $ 5,671
Recorded investment for which there is a related allowance |  | 375 | [1] | 1,045 | [1] | 1,114
Related allowance |  | 18 |  | 75 |  | 110
Recorded investment for which there is no related allowance |  | 4,564 | [1] | 3,858 | [1] | $ 4,557
Consumer Real Estate Portfolio Segment [Member] | Investor Owned Residential Real Estate [Member] |  |  |  |  |  |
Principal balance | [2] | 193 |  | 194 |  |
Total recorded investment | [1],[2] | 193 |  | 194 |  |
Recorded investment for which there is a related allowance | [1],[2] | 193 |  | 194 |  |
Related allowance | [2] | 2 |  | 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] | 3,846 |  | 3,752 |  |
Total recorded investment | [1],[2] | 3,265 |  | 3,202 |  |
Recorded investment for which there is no related allowance | [1],[2] | 3,265 |  | 3,202 |  |
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Other [Member] |  |  |  |  |  |
Principal balance | [2] | 654 |  | 654 |  |
Total recorded investment | [1],[2] | 654 |  | 654 |  |
Recorded investment for which there is no related allowance | [1],[2] | 654 |  | 654 |  |
Commercial Non Real Estate Segment [Member] | Commercial and Industrial [Member] |  |  |  |  |  |
Principal balance | [2] | 826 |  | 851 |  |
Total recorded investment | [1],[2] | 826 |  | 851 |  |
Recorded investment for which there is a related allowance | [1],[2] | 182 |  | 851 |  |
Related allowance | [2] | 16 |  | 73 |  |
Consumer Non Real Estate Portfolio Segment [Member] | Automobile Loan [Member] |  |  |  |  |  |
Principal balance | [2] | 1 |  | 2 |  |
Total recorded investment | [1],[2] | 1 |  | 2 |  |
Recorded investment for which there is no related allowance | [1],[2] | $ 1 |  | $ 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=121611835&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=121611835&loc=d3e5212-111524 + Details
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