Note 9 - Equity Compensation - Summary of Unvested Stock Options (Details) - $ / shares	12 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Unvested (in shares)	1,474,125
Unvested (in dollars per share)	$ 2.65
Granted (in shares)	972,900	794,537
Granted (in dollars per share)	$ 1.48	$ 1.73
Vested (in shares)	(786,536)
Vested (in dollars per share)	$ 2.91
Forfeited (in shares)	(644,334)
Forfeited (in dollars per share)	$ 1.93
Unvested (in shares)	1,016,155	1,474,125
Unvested (in dollars per share)	$ 1.79	$ 2.65