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Note 5 - Fair Value Measurements - Fair Value Quantitative Information (Details) - Fair Value, Nonrecurring [Member] - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2021 | Dec. 31, 2020
Estimated Fair Value | $ 9,126 | $ 10,524
Fair Value, Inputs, Level 3 [Member] |  |
Estimated Fair Value | 9,126 | 10,524
Appraisal Valuation [Member] | Fair Value, Inputs, Level 3 [Member] | Impaired Loan [Member] |  |
Estimated Fair Value | 8,899 | 10,306
Appraisal Valuation [Member] | Fair Value, Inputs, Level 3 [Member] | Other Real Estate Owned [Member] |  |
Estimated Fair Value | $ 227 | $ 218
Appraisal Valuation [Member] | Fair Value, Inputs, Level 3 [Member] | Other Real Estate Owned [Member] | Minimum [Member] |  |
Unobservable Inputs, Rate | 6.00% | 6.00%
Appraisal Valuation [Member] | Fair Value, Inputs, Level 3 [Member] | Other Real Estate Owned [Member] | Maximum [Member] |  |
Unobservable Inputs, Rate | 8.00% | 8.00%
Appraisal Valuation [Member] | Fair Value, Inputs, Level 3 [Member] | Other Real Estate Owned [Member] | Weighted Average [Member] |  |
Unobservable Inputs, Rate | (7.00%) | (7.00%)

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- Definition Percentage of estimation of value used as an input to measure fair value. + References No definition available. + Details
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- Definition Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
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