STOCKHOLDERS' EQUITY - Summary of Stock Option Activity (Detail) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2018 USD ($) $ / shares shares
Stock Options
Outstanding, beginning balance (in shares) | shares	727
Granted (in shares) | shares	0
Exercised (in shares) | shares	(98)
Forfeited (in shares) | shares	0
Outstanding, ending balance (in shares) | shares	669
Exercisable (in shares) | shares	669
Weighted Average Exercise Price
Outstanding, beginning balance (in dollars per share) | $ / shares	$ 5.82
Granted (in dollars per share) | $ / shares	0.00
Exercised (in dollars per share) | $ / shares	4.80
Forfeited (in dollars per share) | $ / shares	0.00
Outstanding, ending balance (in dollars per share) | $ / shares	6.37
Exercisable (in dollars per share) | $ / shares	$ 6.37
Weighted average remaining contractual term, outstanding	5 years 6 months 23 days
Weighted average remaining contractual term, exercisable	5 years 6 months 23 days
Aggregate intrinsic value, outstanding | $	$ 14,788
Aggregate intrinsic value, exercisable | $	$ 14,788
Market-based Performance Stock Options
Stock Options
Market-based stock options vested (in shares) | shares	40
Weighted Average Exercise Price
Market-based stock options vested (in dollars per share) | $ / shares	$ 12.48
Weighted average remaining contractual term, vested	7 years 10 months 23 days
Attainment level percentage	100.00%