Property and Equipment, Net - Components of Property and Equipment (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Property and equipment, cost	$ 697,919	$ 695,008
Accumulated depreciation	(571,317)	(566,623)
Property and equipment, net	126,602	128,385
Computer hardware
Property, Plant and Equipment [Line Items]
Property and equipment, cost	166,657	164,547
Computer software
Property, Plant and Equipment [Line Items]
Property and equipment, cost	292,958	291,681
Furniture and equipment
Property, Plant and Equipment [Line Items]
Property and equipment, cost	88,030	88,136
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, cost	$ 150,274	$ 150,644