Note 15 - Subsequent Events (Details Textual) - USD ($)				3 Months Ended		13 Months Ended
	May 24, 2021	May 19, 2021	Jul. 10, 2017	Mar. 31, 2021	Mar. 31, 2020	May 14, 2021	Dec. 31, 2020	Dec. 31, 2019
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)				$ 2.14	$ 0.50		$ 1.49	$ 0.50
Proceeds from Warrant Exercises				$ 3,012,216	$ 230,362
Previous President and Chief Executive Officer [Member]
Increase (Decrease) in Deferred Compensation			$ 100,000
Employment Agreement, Base Compensation			200,000
Consultant [Member]
Increase (Decrease) in Deferred Compensation			100,000
Employment Agreement, Base Compensation			$ 200,000
Stock Issued During Period, Shares, Issued for Services (in shares)			2,000,000
Compensation Agreement, Term (Year)			5 years
Chief Financial Officer [Member] | Forecast [Member]
Employment Agreement, Base Compensation	$ 200,000
Subsequent Event [Member] | Chief Executive Officer [Member]
Employment Agreement, Base Compensation		$ 350,000
Employment Agreement, Annual Bonuses		$ 400,000
Warrants with 0.50 Exercise Price [Member] | Subsequent Event [Member]
Stock Issued During Period Shares, Warrants Exercised (in shares)						52,000
Warrants with 1.20 Exercise Price [Member] | Subsequent Event [Member]
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)						$ 1.20
Proceeds from Warrant Exercises						$ 62,400
Warrants with 2.60 Exercise Price [Member] | Subsequent Event [Member]
Stock Issued During Period Shares, Warrants Exercised (in shares)						25,000
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)						$ 2.60
Proceeds from Warrant Exercises						$ 65,000