Property and Equipment - Schedule of Property and Equipment, Net (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Property and Equipment [Line Items]
Property and equipment, gross	$ 685,829	$ 480,237
Less: Accumulated depreciation	(338,613)	(235,113)
Total property and equipment, net	347,216	245,124	[1]
Computer equipment
Property and Equipment [Line Items]
Property and equipment, gross	493,536	326,378
Computer software
Property and Equipment [Line Items]
Property and equipment, gross	58,303	46,413
Leasehold and other improvements
Property and Equipment [Line Items]
Property and equipment, gross	74,721	56,232
Furniture and fixtures
Property and Equipment [Line Items]
Property and equipment, gross	42,551	38,789
Building
Property and Equipment [Line Items]
Property and equipment, gross	6,551	7,084
Construction in progress
Property and Equipment [Line Items]
Property and equipment, gross	$ 10,167	$ 5,341

[1] As adjusted to reflect the impact of the full retrospective adoption of Topic 606.