Convertible Notes, Net - Summary of Details of Net Book Value of Convertible Note (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Deferred financing costs	$ (16,327)	$ (21,633)
Net book value	616,389	613,071
Convertible Senior Note [Member]
Debt Instrument [Line Items]
Face Value	622,500	622,500
Unamortized discount	(5,715)	(8,801)
Deferred financing costs	(396)	(628)
Net book value	$ 616,389	$ 613,071