Note 11 - Stock Options (Details) - USD ($)	3 Months Ended			6 Months Ended
	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Text Block [Abstract]
Stock option authorized	5,000,000			5,000,000
Options exercisable weighted average remaining contractual term				2 years 7 months 6 days
Options outstanding weighted average remaining contractual term				2 years 7 months 6 days
Options exercisable, Intrinsic Value	$ 313,314			$ 313,314
Options outstanding, Intrinsic Value	313,314			313,314
Share-based compensation	290,757	$ 113,247		404,004
Unrecognized share-based compensation cost	$ 2,701,689			$ 2,701,689
Unrecognized weighted-average period				2 years 7 months 6 days