Convertible Notes, Net - Summary of Details of Net Book Value of Convertible Note (Detail) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Deferred financing costs	$ (17,941)	$ (16,327)
Net book value	617,242	616,389
Convertible Senior Note [Member]
Debt Instrument [Line Items]
Face Value	622,500	622,500
Unamortized discount	(4,922)	(5,715)
Deferred financing costs	(336)	(396)
Net book value	$ 617,242	$ 616,389

Including the current and noncurrent portions, carrying value as of the balance sheet date of a written promise to pay a note, initially due after one year or beyond the operating cycle if longer, which can be exchanged for a specified amount of one or more securities (typically common stock), at the option of the issuer or the holder.

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