Note 4 - Cash, Cash Equivalents and Marketable Securities - Marketable Securities (Details) - USD ($)	Jun. 30, 2022	Dec. 31, 2021
Amortized cost	$ 22,661,264
Commercial paper	25
Commercial paper	(86,608)
Fair Value	22,574,681	$ 0
Commercial Paper, Not Included with Cash and Cash Equivalents [Member]
Amortized cost	17,658,057
Commercial paper	25
Commercial paper	(57,001)
Fair Value	17,601,081
US Treasury Securities [Member]
Amortized cost	5,003,207
Commercial paper	0
Commercial paper	(29,607)
Fair Value	$ 4,973,600

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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