Property and Equipment, Net - Components of Property and Equipment (Detail) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Property and equipment, cost	$ 855,268	$ 834,232
Accumulated depreciation	(727,280)	(709,056)
Property and equipment, net	127,988	125,176
Computer hardware
Property, Plant and Equipment [Line Items]
Property and equipment, cost	183,287	177,237
Computer software
Property, Plant and Equipment [Line Items]
Property and equipment, cost	378,948	378,734
Furniture and equipment
Property, Plant and Equipment [Line Items]
Property and equipment, cost	112,506	107,421
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, cost	168,881	160,521
Other
Property, Plant and Equipment [Line Items]
Property and equipment, cost	$ 11,646	$ 10,319

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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