Balance Sheet Components - Components of Property and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 55,645	$ 62,162
Less: Accumulated depreciation and amortization	(52,023)	(56,685)
Property and equipment, net	3,622	5,477
Software, Including Internally Developed Software [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 31,220	29,843
Estimated useful life	3 years
Computer Equipment [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 14,967	21,400
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
Finance Lease ROU Assets [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 3,714	5,067
Estimated useful life	4 years
Leasehold Improvements [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 4,138	4,181
Office Equipment, Furniture and Fixtures [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 1,606	$ 1,671
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

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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