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Note 5 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans - Restructurings By Class (Details) $ in Thousands | 12 Months Ended
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Dec. 31, 2021 USD ($) | Dec. 31, 2020
Number of contracts |  | 3 | 0
Pre-modification outstanding principal balance |  | $ 2,826 |
Post-modification outstanding principal balance | [1] | $ 2,826 |
Commercial Real Estate Portfolio Segment [Member] |  |  |
Number of contracts |  | 1 |
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate, Owner Occupied [Member] |  |  |
Number of contracts |  | 1 |
Pre-modification outstanding principal balance |  | $ 102 |
Post-modification outstanding principal balance | [1] | $ 102 |
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Other [Member] |  |  |
Number of contracts |  | 2 |
Pre-modification outstanding principal balance |  | $ 2,724 |
Post-modification outstanding principal balance |  | $ 2,724 |
[1] | Post-modification outstanding recorded investment considers amounts immediately following the modification. Amounts do not reflect balances at the end of the period.

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- Definition Number of financing receivables that have been modified by troubled debt restructurings. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524 + Details
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- Definition Amount, after troubled debt restructuring, of modified financing receivable. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524 + Details
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- Definition Amount, before troubled debt restructuring, of financing receivable to be modified. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524 + Details
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