Balance Sheet Components - Schedule of Property and Equipment Net (Details) - USD ($) $ in Thousands	Jul. 31, 2019	Jan. 31, 2019
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 70,566	$ 48,743
Less: accumulated depreciation and amortization	(18,579)	(11,468)
Property and equipment, net	51,987	37,275
Computer and Office Equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	43,877	32,515
Leasehold Improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	15,290	7,660
Software
Property, Plant and Equipment [Line Items]
Property and equipment, gross	7,941	6,575
Furniture and Fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 3,458	$ 1,993

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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