Property and Equipment, Net - Summary of Property and Equipment, Net (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 252,712	$ 266,346
Less: Accumulated depreciation	(227,807)	(221,291)
Total property and equipment, net	24,905	45,055
Computer software and web development [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	229,855	229,527
Computer Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	16,973	23,738
Building [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	0	5,158
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	4,600	4,600
Furniture, fixtures and equipment [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	1,166	1,166
Computer Software and Web Development Projects In-process [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 118	$ 2,157