Property and Equipment, Net - Components of Property and Equipment, Net (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Property Plant And Equipment [Line Items]
Total property and equipment	$ 73,666	$ 53,487
Less: accumulated depreciation and amortization	(31,607)	(20,738)
Total property and equipment, net	42,059	32,749
Computers and Equipment
Property Plant And Equipment [Line Items]
Total property and equipment	10,544	7,536
Furniture and Fixtures
Property Plant And Equipment [Line Items]
Total property and equipment	5,090	4,804
Leasehold Improvements
Property Plant And Equipment [Line Items]
Total property and equipment	17,510	16,517
Capitalized Software Development Costs
Property Plant And Equipment [Line Items]
Total property and equipment	$ 40,522	$ 24,630