Note 4 - Cash, Cash Equivalents and Marketable Securities (Tables)

3 Months Ended

Mar. 31, 2022

Notes Tables

Schedule of Cash and Cash Equivalents [Table Text Block]

	March 31, 2022		December 31, 2021
Cash in banking institutions	$	1,326,178	$	30,308,075
Money market funds		5,046,607		7,005,483
Commercial paper		3,499,545		—
Total	$	9,872,330	$	37,313,558

Debt Securities, Available-for-Sale [Table Text Block]

	Amortized cost		Unrealized gains		Unrealized losses			Fair Value
Commercial paper	$	19,716,092	$	—	$	(39,939	)	$	19,676,153
U.S. treasury bonds		3,013,869		—		(9,719	)		3,004,150
Total	$	22,729,961	$	—	$	(49,658	)	$	22,680,303