Balance Sheet Components - Schedule of Property and Equipment, Net (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 65,847	$ 52,765
Less: accumulated depreciation and amortization	(25,420)	(19,479)
Property and equipment, net	40,427	33,286
Proprietary Software
Property Plant And Equipment [Line Items]
Property and equipment, gross	17,939	14,052
Furniture And Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	16,877	12,665
Automobiles
Property Plant And Equipment [Line Items]
Property and equipment, gross	516	346
Leasehold Improvements
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 30,515	$ 25,702

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 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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