Balance Sheet Components - Components of Property and Equipment (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 53,656	$ 53,658
Less: Accumulated depreciation and amortization	(50,262)	(50,262)
Less: Accumulated impairment losses	(3,276)	(3,276)
Property and equipment, net	118	120
Software, Including Internally Developed Software [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 34,972	34,972
Estimated useful life	3 years
Computer Equipment [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 18,078	18,080
Computer Equipment [Member] | Minimum [Member]
Property Plant And Equipment [Line Items]
Estimated useful life	3 years
Computer Equipment [Member] | Maximum [Member]
Property Plant And Equipment [Line Items]
Estimated useful life	4 years
Leasehold Improvements [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 512	512
Office Equipment, Furniture and Fixtures [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 94	$ 94
Office Equipment, Furniture and Fixtures [Member] | Minimum [Member]
Property Plant And Equipment [Line Items]
Estimated useful life	3 years
Office Equipment, Furniture and Fixtures [Member] | Maximum [Member]
Property Plant And Equipment [Line Items]
Estimated useful life	5 years