Note 2 - Liquidity and Capital Resources (Details Textual) - USD ($)	3 Months Ended						9 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Net Income (Loss) Attributable to Parent, Total	$ (3,285,914)	$ (7,262,529)	$ (4,073,307)	$ (3,309,866)	$ (4,142,577)	$ (1,874,382)	$ (14,621,750)	$ (9,326,825)
Net Cash Provided by (Used in) Operating Activities, Total							(6,420,035)	(6,517,985)
Cash and Cash Equivalents, at Carrying Value, Ending Balance	15,289,543			$ 12,935,587			15,289,543	$ 12,935,587	$ 10,380,493
Working Capital	$ 14,800,000						$ 14,800,000