Nature of Business and Summary of Significant Accounting Policies - Summary of Property and Equipment Estimated Useful Lives and Balances (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 188,183	$ 187,793
Less: accumulated depreciation	(125,133)	(123,059)
Property and equipment, net	63,050	64,734
Computer and office equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 127,352	133,346
Computer and office equipment | Minimum
Property, Plant and Equipment [Line Items]
Useful Lives	3 years
Computer and office equipment | Maximum
Property, Plant and Equipment [Line Items]
Useful Lives	5 years
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 34,460	29,535
Useful Lives, description	Lesser of useful life of improvement or remaining life of lease
Building and improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 14,853	14,588
Building and improvements | Minimum
Property, Plant and Equipment [Line Items]
Useful Lives	7 years
Building and improvements | Maximum
Property, Plant and Equipment [Line Items]
Useful Lives	30 years
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 9,733	8,539
Useful Lives	7 years
Land
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 1,785	$ 1,785
Useful Lives, description	Non-depreciable