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Note 8 - Investments, Including Investments Accounted for Using the Equity Method - Trading Securities (Details) - USD ($) | Jun. 30, 2020 | Dec. 31, 2019
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Marketable equity securities, Cost | $ 69,318,420 | $ 49,554,926
Marketable equity securities, Gross Unrealized Gain (Loss) | (18,788,834) | 6,353,001
Marketable equity securities | $ 50,529,586 | $ 55,907,927

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- Definition The accumulated unrealized gain (loss) on equity securities. + References No definition available. + Details
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- Definition Amount of 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/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 45 -Paragraph 1A -URI http://asc.fasb.org/extlink&oid=99377092&loc=SL75136599-209740 + Details
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- Definition Cost of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). Excludes equity method investment and investment in equity security without readily determinable fair value. + References No definition available. + Details
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