Income Taxes - Reconciliation of Federal Statutory Income Tax Rate to Effective Tax Rate (Detail)		1 Months Ended	12 Months Ended
		Apr. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Federal statutory income tax rate			19.00%	19.00%	19.00%
Tax effect of international operations	[1]		(3.90%)	(8.20%)	(9.90%)
Change in valuation allowances			1.30%	1.10%	7.90%
Excess tax benefits on stock-based compensation			(0.70%)	(0.70%)	(1.70%)
Base erosion and anti-abuse tax		0.003	0.017	0	0
Tax effect of U.S. tax reform			0.00%	0.00%	(0.90%)
Tax effect of early extinguishment of debt			0.00%	0.00%	0.90%
Effective tax rate			17.40%	11.20%	15.30%

[1] The tax effect of international operations consists of non-U.K. jurisdictions.