STOCKHOLDERS’ EQUITY - Narrative (Detail) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019 USD ($) $ / shares shares	Jun. 30, 2018 USD ($)	Jun. 30, 2019 USD ($) vote $ / shares shares	Jun. 30, 2018 USD ($) shares	May 29, 2019 $ / shares shares	Dec. 31, 2018 $ / shares shares	Oct. 26, 2018 $ / shares
Class of Stock [Line Items]
Common stock, par value (usd per share) | $ / shares	$ 0.00001		$ 0.00001			$ 0.00001
Common stock, shares authorized (in shares)	400,000,000		400,000,000			400,000,000
Preferred stock, shares authorized (in shares)	50,000,000		50,000,000		50,000,000	50,000,000
Preferred stock, par value (usd per share) | $ / shares	$ 0.00001		$ 0.00001		$ 0.00001	$ 0.00001
Stock Repurchase Program, Increase (Decrease) [Roll Forward]
Amount available for repurchase — beginning of period | $	$ 79,598	$ 95,902	$ 57,437	$ 95,902
Additional amount authorized for repurchase | $	0	0	100,000	100,000
Repurchase of common stock | $	(79,600)	0	(157,439)	(100,000)
Amount available for repurchase — end of period | $	$ 0	$ 95,902	$ 0	$ 95,902
Repurchase of common stock (in shares)	4,012,469		8,389,348
Class A Common Stock
Class of Stock [Line Items]
Common stock, par value (usd per share) | $ / shares					$ 0.00001		$ 0.00001
Common stock, shares authorized (in shares)					400,000,000
Stock Repurchase Program, Increase (Decrease) [Roll Forward]
Common Stock, Number of Voting Rights | vote			1
Repurchase of common stock (in shares)				7,588,771
Class B Common Stock
Class of Stock [Line Items]
Common stock, par value (usd per share) | $ / shares							$ 0.00001
Stock Repurchase Program, Increase (Decrease) [Roll Forward]
Common Stock, Number of Voting Rights | vote			1