STOCKHOLDERS' EQUITY - Summary of Restricted Stock, Restricted Stock Unit and Performance Stock Unit Activity (Detail) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2019 USD ($) $ / shares shares
Restricted Stock, Restricted Stock Units and Performance Stock Units
Restricted Stock, Restricted Stock Units, and Performance Stock Units
Outstanding, beginning balance (in shares)	686,000
Granted (in shares)	166,000
Vested (in shares)	(449,000)
Forfeited or canceled (in shares)	(10,000)
Outstanding, ending balance (in shares)	393,000
Unvested, ending balance (in shares)	579,000
Weighted Average Grant Price
Outstanding, beginning balance (in dollars per share) | $ / shares	$ 15.56
Granted (in dollars per share) | $ / shares	37.24
Vested (in dollars per share) | $ / shares	12.38
Forfeited or canceled (in dollars per share) | $ / shares	23.41
Outstanding, ending balance (in dollars per share) | $ / shares	28.23
Weighted average grant price, unvested, ending balance (in dollars per share) | $ / shares	$ 29.69
Weighted average remaining contractual term, outstanding	1 year 3 months 18 days
Weighted average remaining contractual term, unvested	1 year 4 months 24 days
Aggregate intrinsic value, outstanding | $	$ 6,992
Aggregate intrinsic value, unvested | $	$ 9,458
Performance Stock Units
Weighted Average Grant Price
Attainment level percentage	100.00%
Class A Common Stock | Performance Stock Units
Weighted Average Grant Price
Additional issuance if performance targets met (in shares)	186,000
Additional shares issued	178,000