STOCK-BASED COMPENSATION - SCHEDULE OF INFORMATION REGARDING RESTRICTED STOCK UNITS OUTSTANDING (Detail) - RSUs outstanding - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
RSUs outstanding, number (in shares)	1,090,938	508,880
RSUs vested and expected to vest using estimated forfeiture rates, number (in shares)	915,934
RSUs outstanding, weighted average remaining contractual life (years)	10 months 24 days
RSUs vested and expected to vest using estimated forfeiture rates, Weighted Average Remaining Contractual Life (years)	9 months 18 days
RSUs outstanding, aggregate intrinsic value (in dollars)	$ 11.5
RSUs vested and expected to vest using estimated forfeiture rates, aggregate intrinsic value (in dollars)	$ 9.7