Property and Equipment, Net - Schedule of Property and Equipment, Net (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2021	Dec. 31, 2020
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 367,539	$ 367,614
Accumulated depreciation	(256,922)	(246,587)
Property and equipment, net	110,617	121,027
Buildings and Leasehold Improvements
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 97,167	98,151
Buildings and Leasehold Improvements \| Minimum
Property Plant And Equipment [Line Items]
Useful life (years)	1 year
Buildings and Leasehold Improvements \| Maximum
Property Plant And Equipment [Line Items]
Useful life (years)	15 years
Furniture and Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 88,403	91,036
Furniture and Equipment \| Minimum
Property Plant And Equipment [Line Items]
Useful life (years)	3 years
Furniture and Equipment \| Maximum
Property Plant And Equipment [Line Items]
Useful life (years)	10 years
Computer Systems and Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 164,302	160,305
Computer Systems and Equipment \| Minimum
Property Plant And Equipment [Line Items]
Useful life (years)	3 years
Computer Systems and Equipment \| Maximum
Property Plant And Equipment [Line Items]
Useful life (years)	10 years
Construction Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 8,635	8,920
Construction Equipment \| Minimum
Property Plant And Equipment [Line Items]
Useful life (years)	5 years
Construction Equipment \| Maximum
Property Plant And Equipment [Line Items]
Useful life (years)	7 years
Construction in Progress
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 9,032	$ 9,202

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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