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]
Total property and equipment	$ 73,426	$ 44,944
Accumulated depreciation and amortization	(25,024)	(19,680)
Property and Equipment, net	48,402	25,264
Computer and Equipment
Property Plant And Equipment [Line Items]
Total property and equipment	19,981	16,056
Leasehold Improvements
Property Plant And Equipment [Line Items]
Total property and equipment	39,293	18,396
Website and Internal-Use Software
Property Plant And Equipment [Line Items]
Total property and equipment	6,507	6,423
Office Equipment and Furniture
Property Plant And Equipment [Line Items]
Total property and equipment	$ 7,645	$ 4,069

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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