Note 14 - Stock Based Compensation - Stock-based Compensation Expense (Details) - USD ($)	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Stock compensation expense	$ 1,794,138	$ 663,593	$ 3,647,999	$ 2,387,829
General and Administrative Expense [Member]
Stock compensation expense	1,231,590	489,853	2,534,117	1,675,414
Research and Development Expense [Member]
Stock compensation expense	$ 562,548	$ 173,740	$ 1,113,882	$ 712,415

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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