Balance Sheet Components - Schedule of Property and Equipment (Details) - USD ($) $ in Thousands	Jan. 31, 2020	Jan. 31, 2019
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 84,394	$ 48,743
Less: accumulated depreciation and amortization	(27,256)	(11,468)
Property and equipment, net	57,138	37,275
Machinery and Equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	51,375	32,515
Leasehold Improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	18,215	7,660
Software
Property, Plant and Equipment [Line Items]
Property and equipment, gross	10,855	6,575
Furniture and Fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 3,949	$ 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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