Balance Sheet Components - Schedule of Property and Equipment, Net (Details) - USD ($) $ in Thousands	Jul. 31, 2018	Jan. 31, 2018
Property Plant And Equipment [Line Items]
Total property and equipment, gross	$ 302,617	$ 279,181
Less: accumulated depreciation	(177,260)	(155,204)
Total property and equipment, net	125,357	123,977
Servers
Property Plant And Equipment [Line Items]
Total property and equipment, gross	186,205	170,422
Leasehold improvements
Property Plant And Equipment [Line Items]
Total property and equipment, gross	75,307	72,599
Computer hardware and software
Property Plant And Equipment [Line Items]
Total property and equipment, gross	15,920	14,558
Furniture and fixtures
Property Plant And Equipment [Line Items]
Total property and equipment, gross	15,288	14,254
Construction in progress
Property Plant And Equipment [Line Items]
Total property and equipment, gross	$ 9,897	$ 7,348

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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