RESTATEMENT OF CONSOLIDATED FINANCIAL STATEMENTS - Additional Information (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Jul. 01, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Accumulated deficit	$ (264,400)	$ (232,372)	$ (232,748)	$ (231,052)	$ (227,829)	$ (223,635)	$ (221,531)	$ (218,593)	$ (217,668)	$ (217,436)
Decrease in deferred income taxes											$ (2,300)
Adjustments
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Accumulated deficit				$ (36,191)	$ (31,808)	$ (40,130)	$ (38,172)	$ (34,991)	$ (33,930)	$ (33,465)	(32,600)
Decrease in deferred income taxes											$ 27,800