Property and Equipment - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Property Plant And Equipment [Line Items]
Gross carrying amount property and equipment	$ 468,528		$ 442,527
Accumulated amortization	250,851		226,381
Depreciation and amortization	37,717	$ 33,363
Capitalized developed software costs	19,200	19,000
Property And Equipment Excluding Developed Software
Property Plant And Equipment [Line Items]
Depreciation and amortization	12,300	8,700
Developed Software \| Disposal Group, Disposed of by Means Other than Sale, Not Discontinued Operations
Property Plant And Equipment [Line Items]
Gross carrying amount property and equipment	3,500
Accumulated amortization	3,500
Developed software
Property Plant And Equipment [Line Items]
Gross carrying amount property and equipment	239,276		$ 223,596
Depreciation and amortization	$ 15,700	$ 12,000

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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Additions made to capitalized computer software costs during the period.

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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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