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Note 9 - Investments, Including Investments Accounted for Using the Equity Method (As Restated) - Marketable Equity Securities and Trading Securities (Details) - USD ($)	Dec. 31, 2020	Dec. 31, 2019
Marketable equity securities, Cost	$ 68,205,548	$ 49,554,926
Marketable equity securities, Gross Unrealized Gain (Loss)	(4,169,066)	6,353,001
Marketable equity securities	64,036,482	55,907,927
U.S. Treasury trading securities, fair value	37,767,945	75,409,199
US Treasury Notes Securities [Member]
U.S. Treasury trading securities, cost	37,766,133	75,488,863
U.S. Treasury trading securities, gross unrealized gain (loss)	1,812	(79,664)
U.S. Treasury trading securities, fair value	$ 37,767,945	$ 75,409,199

X

- Definition

Amount, before tax, of unrealized gain (loss) on investment in debt security classified as trading.

+ References

No definition available.

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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

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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.

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- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121553693&loc=d3e26610-111562

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=121553693&loc=d3e26610-111562

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- Definition

Amortized cost of investments in debt securities classified as trading.

+ References

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