Income Taxes - Reconciliation of Statutory Tax Rate to Effective Tax Rate (Detail)		12 Months Ended
		Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
U.S. federal statutory income tax rate		21.00%	21.00%	21.00%
State and local income taxes, net of federal benefit		(5.30%)	(15.70%)	1.70%
Foreign income at other than U.S. rates	[1]	14.20%	10.90%	10.50%
Stock-based compensation		(29.90%)	(59.60%)	(20.50%)
Meals and entertainment		0.20%	0.20%	0.70%
Nondeductible compensation		1.70%	0.60%	(1.30%)
Research and development credit		(15.30%)	(14.10%)	(5.00%)
Other permanent items		0.50%	0.10%	(0.30%)
Benefit from carryback of NOLs			(11.80%)
Effective income tax rate		(12.90%)	(68.40%)	6.80%

[1] For the years ended December 31, 2021, 2020, and 2019, includes the impact of the valuation allowance associated with the United Kingdom (“U.K.”). For additional information, see discussion below.