Note 7 - Investments in Equity Securities (Details Textual) - USD ($)	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020
Equity Securities, FV-NI, Unrealized Gain	$ 0	$ 0
Equity Securities, FV-NI, Unrealized Loss	265,941	28,093
Equity Securities, FV-NI, Realized Gain	152,748	0
Equity Securities, FV-NI, Realized Loss	$ 0	$ 0

Amount of realized gain from sale of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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=123583765&loc=SL75117546-209714

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Balance Type:	credit
Period Type:	duration

- Definition

Amount of realized loss from sale of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of unrealized gain 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/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=123583765&loc=SL75117546-209714

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

Amount of unrealized loss on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

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