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Note 8 - Investments, Including Investments Accounted for Using the Equity Method - Trading Securities (Details) - USD ($) | Dec. 31, 2019 | Dec. 31, 2018
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Marketable equity securities, Cost | $ 49,554,926 |
Marketable equity securities, Gross Unrealized Gain (Loss) | 6,353,001 |
Marketable equity securities | $ 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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