STOCK BASED COMPENSATION - Option activity for company's stock incentive plans (Detail) - USD ($) $ / shares in Units, $ in Thousands	6 Months Ended	12 Months Ended
	Dec. 31, 2017	Jun. 30, 2017
Number of Shares
Beginning balance (in shares)	1,621,601
Exercised (in shares)	(97,667)
Ending balance (in shares)	1,523,934	1,621,601
Number of shares, vested, ending balance (in shares)	1,523,934
Number of shares, vested and exercisable, ending balance (in shares)	1,523,934
Weighted Average Exercise Price
Beginning balance (in usd per share)	$ 1.76
Exercised (in usd per share)	8.70
Ending balance (in usd per share)	1.32	$ 1.76
Options, weighted average exercise price, vested, ending balance (in usd per share)	1.32
Options, weighted average exercise price, vested and exercisable, ending balance (in usd per share)	$ 1.32
Options outstanding, weighted average remaining contractual term, ending balance (in years)	9 months 26 days	1 year 6 months 18 days
Options, remaining contractual term, vested, ending balance (in years)	9 months 26 days
Options, weighted average remaining contractual term, vested and exercisable, ending balance (in years)	9 months 26 days
Options outstanding, intrinsic value, ending balance	$ 106,218	$ 81,413
Options, aggregate intrinsic value, vested, ending balance	106,218
Options, aggregate intrinsic value, vested and exercisable, ending balance	$ 106,218