Property and Equipment, Net - Schedule of Property and Equipment, Net (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 62,056	$ 53,477
Less accumulated depreciation and amortization	(32,487)	(25,994)
Property and equipment, net	29,569	27,483
Computer Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	8,604	8,108
Capitalized Software
Property Plant And Equipment [Line Items]
Property and equipment, gross	149	149
Capitalized Website Development
Property Plant And Equipment [Line Items]
Property and equipment, gross	19,451	16,328
Furniture and Fixtures
Property Plant And Equipment [Line Items]
Property and equipment, gross	8,491	7,320
Leasehold Improvements
Property Plant And Equipment [Line Items]
Property and equipment, gross	24,086	20,507
Construction in Progress
Property Plant And Equipment [Line Items]
Property and equipment, gross	665	1,024
Finance Lease Right-of-use Assets
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 610	$ 41

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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