Condensed Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) - $ / shares	Mar. 31, 2022	Jun. 30, 2021
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized (in shares)	2,500,000	2,500,000
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	250,000,000	50,000,000
Common stock, shares issued (in shares)	49,569,113	49,450,558
Common stock, shares outstanding (in shares)	49,569,113	49,450,558
Series D Preferred Stock [Member]
Preferred stock, shares issued (in shares)	280,898	280,898
Preferred stock, shares outstanding (in shares)	280,898	280,898