INCOME TAXES - Summary of Net Deferred Tax Assets (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Jun. 30, 2020
Deferred tax assets:
Net operating loss carryforwards	$ 46,851	$ 45,670
Asset reserves	7,231	8,534
Deferred research and development	1,420	1,625
Stock-based compensation	2,620	668
Other	2,135	1,485
Deferred tax assets, gross	60,257	57,982
Deferred tax liabilities:
Intangibles	(4,956)	(5,566)
Deferred tax assets, net	55,301	52,416
Valuation allowance	(55,480)	(52,553)
Deferred tax liabilities	$ (179)	$ (137)