Note 9 - Per Share Data - Reconciliation of the Basic and Diluted Loss Per Share (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Net income (loss)	$ 2,037,062	$ 169,200	$ 1,676,012	$ (642,905)
Less: Change in fair value of warrants and cash-based RSUs	49,559	428,128	400,663	1,346,929
Net income/(loss), adjusted for change in fair value of warrants and cash-based RSUs for diluted earnings per share	$ 1,987,503	$ (258,928)	$ 1,275,349	$ (1,989,834)
Weighted average shares outstanding: basic (in shares)	72,678,333	75,810,641	72,873,366	76,281,211
Effect of potential common shares (in shares)	654,555	849,413	825,860	847,762
Weighted average shares outstanding: diluted (in shares)	73,332,888	76,660,054	73,699,226	77,128,973
Basic income/(loss) per share (in dollars per share)	$ 0.03	$ 0.00	$ 0.02	$ (0.01)
Diluted income/(loss) per share (in dollars per share)	$ 0.03	$ (0.00)	$ 0.02	$ (0.03)