Income Taxes - Schedule of Differences Between Income Taxes Computed at the Federal Statutory Rate and the Provision for Income Taxes (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Expected income tax benefit at the federal statutory rate	$ 10,665	$ 12,955	$ 17,166
State taxes net of federal benefit	3,700	5,155	5,150
Stock-based compensation	16,055	17,575	10,939
Executive compensation limitation	(7,244)
Difference in foreign tax rates	693	435	988
U.S. tax credits	24,170	1,763	1,717
Convertible debt and acquisition			11,573
Federal rate change			(49,123)
Transition tax			(1,063)
GILTI inclusion	(1,645)	(1,177)
Meals and entertainment	(1,208)	(1,411)	(745)
Change in valuation allowance	(47,523)	(37,059)	13,988
Other	(636)	(104)	(265)
Total income tax benefit (provision)	$ (2,973)	$ (1,868)	$ 10,325