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Note 7 - Investments, Including Investments Accounted for Using the Equity Method - Marketable Equity Securities and Trading Securities (Details) - USD ($) | Sep. 30, 2025 | Dec. 31, 2024
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Marketable equity securities, Cost | $ 1,074,439 | $ 2,455,024
Marketable equity securities, Gross Unrealized Gain (Loss) | (76,992) | (61,764)
Marketable equity securities | $ 997,447 | $ 2,393,260

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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), classified as current. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 825 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 1A -Publisher FASB -URI https://asc.fasb.org/1943274/2147482736/825-10-45-1A Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(2)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Subparagraph (f) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483467/210-10-45-1 + Details
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