STOCK-BASED COMPENSATION - SCHEDULE OF INFORMATION REGARDING STANDARD AND MARKET CONDITION BASED STOCK OPTIONS OUTSTANDING (Detail) - USD ($) $ / shares in Units, $ in Millions	9 Months Ended
	Sep. 30, 2018	Dec. 31, 2017
Standard Stock Options
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Common stock options outstanding (in shares)	2,050,436	3,277,991
Options vested and expected to vest using estimated forfeiture rates, number (in shares)	1,956,894
Options exercisable, number (in shares)	1,511,605
Options outstanding, Weighted Average Exercise Price (in dollars per share)	$ 9.31
Options vested and expected to vest using estimated forfeiture rates, Weighted Average Exercise Price (in dollars per share)	9.27
Options exercisable, Weighted Average Exercise Price (in dollars per share)	$ 9.11
Options outstanding, Weighted Average Remaining Contractual Life (years)	2 years 11 months 19 days
Options vested and expected to vest using estimated forfeiture rates, Weighted Average Remaining Contractual Life (years)	2 years 9 months 25 days
Options exercisable, weighted average remaining contractual (years)	2 years
Options outstanding, aggregate intrinsic value (in dollars)	$ 3.3
Options vested and expected to vest using estimated forfeiture rates, Aggregate Intrinsic Value (in dollars)	3.1
Options exercisable, aggregate intrinsic value (in dollars)	$ 2.5
Market Condition Based Stock Options
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Common stock options outstanding (in shares)	272,081	272,081