Supplemental Financial Statement Information - Property and Equipment (Detail) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 20,836	$ 19,628
Less: Accumulated depreciation and amortization	(17,134)	(16,811)
Property and equipment, net	3,702	2,817
Computer and Other Related Equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	14,536	13,373
Purchased and Internally Developed Software
Property, Plant and Equipment [Line Items]
Property and equipment, gross	2,893	2,483
Furniture and Fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	1,271	1,271
Leasehold Improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	1,732	1,732
Construction in Progress
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 404	$ 769

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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