Note 2 - Liquidity and Capital Resources (Details Textual) - USD ($)	3 Months Ended				6 Months Ended
	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2018	Mar. 31, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Net Income (Loss) Attributable to Parent, Total	$ (7,262,529)	$ (4,073,307)	$ (4,142,577)	$ (1,874,382)	$ (11,335,836)	$ (6,016,959)
Net Cash Provided by (Used in) Operating Activities, Total					(4,651,051)	(4,219,793)
Cash and Cash Equivalents, at Carrying Value, Ending Balance	17,058,527		$ 15,236,736		17,058,527	$ 15,236,736	$ 10,380,493
Working Capital	$ 17,400,000				$ 17,400,000