Note 4 - Cash, Cash Equivalents and Marketable Securities - Marketable Securities (Details) - USD ($)	Mar. 31, 2022	Dec. 31, 2021
Amortized cost	$ 22,729,961
Commercial paper	0
Commercial paper	(49,658)
Fair Value	22,680,303	$ 0
Commercial Paper, Not Included with Cash and Cash Equivalents [Member]
Amortized cost	19,716,092
Commercial paper	0
Commercial paper	(39,939)
Fair Value	19,676,153
US Treasury Securities [Member]
Amortized cost	3,013,869
Commercial paper	0
Commercial paper	(9,719)
Fair Value	$ 3,004,150

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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