Property, Plant and Equipment - Components of Property and Equipment (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Property and equipment—at cost	$ 369,555	$ 350,914
Less: accumulated depreciation	(277,371)	(264,989)
Property and equipment—net	92,184	85,925
Land
Property, Plant and Equipment [Line Items]
Property and equipment—at cost	790	790
Building
Property, Plant and Equipment [Line Items]
Property and equipment—at cost	8,285	8,285
Software
Property, Plant and Equipment [Line Items]
Property and equipment—at cost	118,579	109,546
Computers and office equipment
Property, Plant and Equipment [Line Items]
Property and equipment—at cost	198,338	187,056
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment—at cost	18,926	18,918
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment—at cost	20,497	20,469
Construction in process
Property, Plant and Equipment [Line Items]
Property and equipment—at cost	$ 4,140	$ 5,850

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.

+ References

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