Property, Equipment and Leasehold Improvements, Net - Schedule of Property, Equipment and Leasehold Improvements, Net (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Computer & related equipment	$ 179,557	$ 186,786
Furniture & fixtures	14,194	15,276
Leasehold improvements	56,308	56,537
Work-in-process	2,699	2,996
Subtotal	252,758	261,595
Accumulated depreciation and amortization	(186,043)	(181,149)
Property, equipment and leasehold improvements, net	$ 66,715	$ 80,446
Computer & Related Equipment [Member] \| Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	2 years
Computer & Related Equipment [Member] \| Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	5 years
Furniture & Fixtures [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	7 years
Leasehold improvements [Member] \| Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	1 year
Leasehold improvements [Member] \| Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	21 years

Long lived, depreciable assets that are used in the creation, maintenance and utilization of information systems.

No definition available.

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- Definition

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 of structure or a modification to a structure under construction. Includes recently completed structures or modifications to structures that have not been placed into service.

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- Definition

Amount before accumulated depreciation of equipment commonly used in offices and stores that have no permanent connection to the structure of a building or utilities. Examples include, but are not limited to, desks, chairs, tables, and bookcases.

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Amount before accumulated depreciation of additions or improvements to assets held under a lease arrangement.

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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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services 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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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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