Convertible Notes, Net - Summary of Details of Net Book Value of Convertible Note (Detail) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Deferred financing costs	$ (18,525)	$ (16,327)
Net book value	618,985	616,389
Convertible Senior Note [Member]
Debt Instrument [Line Items]
Face Value	622,500	622,500
Unamortized discount	(3,301)	(5,715)
Deferred financing costs	(214)	(396)
Net book value	$ 618,985	$ 616,389