Note 7 - Marketable Securities (Details Textual) - USD ($)	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Proceeds from Sale and Maturity of Marketable Securities			$ 1,658,292	$ 1,832,827
Debt and Equity Securities, Realized Gain (Loss), Total	$ (207,936)	$ 112,180	$ (207,936)	$ 112,180

The cash inflow associated with the aggregate amount received by the entity through sale or maturity of marketable securities (held-to-maturity or available-for-sale) during the period.

No definition available.

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