Property and Equipment - Schedule of Property and Equipment (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Property Plant And Equipment [Line Items]
Gross property and equipment	$ 72,917	$ 80,793
Less: Accumulated depreciation	(64,721)	(61,869)
Property and equipment, net	8,196	18,924
Computer Equipment
Property Plant And Equipment [Line Items]
Gross property and equipment	7,990	15,770
Leasehold Improvements
Property Plant And Equipment [Line Items]
Gross property and equipment	54,340	54,079
Furniture, Fixtures, and Other Assets
Property Plant And Equipment [Line Items]
Gross property and equipment	$ 10,587	$ 10,944

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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