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Note 3 - Securities (Details Textual) - USD ($) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2019 | Dec. 31, 2020 | Dec. 31, 2019
Pledged Assets Separately Reported, Securities Pledged as Collateral, at Fair Value, Total |  |  | $ 1,200,000 | $ 2,000,000.0
Equity Securities, FV-NI, Gain (Loss), Total | [1] |  | $ 0 | $ 295,000
Visa Inc Class B Common Stock [Member] |  |  |  |
Equity Securities without Readily Determinable Fair Value, Shares Sold (in shares) |  | 25,702 |  |
Equity Securities, FV-NI, Gain (Loss), Total |  | $ 295,000 |  |
[1] | Not within the scope of ASC 606

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- Definition Number of shares sold of investment in equity security without readily determinable fair value. + References No definition available. + Details
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- Definition Amount of unrealized and realized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 321 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=120269885&loc=SL75117546-209714 + Details
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- Definition The sum of the fair values, as of the date of each statement of financial position presented, of securities that are restricted as collateral for the payment of related debt obligations, primarily secured borrowings and repurchase agreements, and that are reclassified and separately reported in the statement of financial position because the transferee has the right by contract or custom to sell or re-pledge them. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=66007379&loc=d3e113888-111728 + Details
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