Balance Sheet Components - Property and Equipment, Net (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Property and equipment, Total	$ 75,830	$ 75,981
Accumulated depreciation and amortization	(64,754)	(63,543)
Projects in process	4,552	1,266
Total property and equipment, net	15,628	13,704
Software
Property, Plant and Equipment [Line Items]
Property and equipment, Total	44,122	41,876
Computer equipment
Property, Plant and Equipment [Line Items]
Property and equipment, Total	23,365	25,773
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, Total	5,867	5,883
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, Total	$ 2,476	$ 2,449

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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Amount of structure or a modification to a structure under construction. Includes recently completed structures or modifications to structures that have not been placed into service.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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