Note 10 - Subsequent Events (Details Textual) - USD ($)	Aug. 12, 2020	Jul. 01, 2020	Apr. 01, 2020
Shares Issued, Price Per Share (in dollars per share)			$ 1.08
Subsequent Event [Member] | Common Stock Warrants [Member]
Stock Issued During Period, Shares, Warrants Exercised (in shares)	27,051
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)	$ 3.46
Class of Warrant or Right, Number of Warrants Exercised (in shares)	60,000
Private Placement [Member] | Subsequent Event [Member]
Stock Issued During Period, Shares, New Issues (in shares)		1,796,407
Shares Issued, Price Per Share (in dollars per share)		$ 1.67
Proceeds from Issuance of Private Placement		$ 3,000,000