Convertible Notes, Net - Summary of Details about Interest Expense (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Discount and issuance cost amortization	$ 32,016	$ 28,097	$ 21,988
Convertible Senior Note [Member]
Debt Instrument [Line Items]
Cash coupon	28,059	33,859	19,259
Discount and issuance cost amortization	3,159	5,531	4,040
Total interest expense	$ 31,218	$ 39,390	$ 23,299