Balance Sheet Components - Schedule of Cost and Accumulated Depreciation and Amortization of Property and Equipment (Details) - USD ($) $ in Thousands	Jan. 31, 2020	Jan. 31, 2019
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 59,397	$ 54,482
Less: accumulated depreciation and amortization	(37,409)	(26,863)
Property and equipment, net	21,988	27,619
Computer equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	22,489	18,259
Furniture and office equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	12,672	11,907
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 24,236	$ 24,316

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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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services 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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