Non-vested Stock Option Activity (Detail) - $ / shares	12 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2018
Number of options
Beginning balance	4,376,928
Granted	3,733,333
Forfeited	(76,563)
Vested	(2,255,791)
Ending balance	5,777,907	4,376,928
Weighted average grant date fair value
Beginning balance	$ 3.51
Granted	2.50	$ 2.78	$ 2.40
Forfeited	2.86
Vested	3.26
Ending balance	$ 2.96	$ 3.51