Balance Sheet Components - Schedule of Property and Equipment, Net (Details) - USD ($) $ in Thousands	Apr. 30, 2017	Jan. 31, 2017
Property Plant And Equipment [Line Items]
Total property and equipment, gross	$ 243,171	$ 237,677
Less: accumulated depreciation	(125,603)	(120,501)
Total property and equipment, net	117,568	117,176
Servers
Property Plant And Equipment [Line Items]
Total property and equipment, gross	145,081	143,219
Leasehold improvements
Property Plant And Equipment [Line Items]
Total property and equipment, gross	64,422	64,379
Computer hardware and software
Property Plant And Equipment [Line Items]
Total property and equipment, gross	11,688	11,373
Furniture and fixtures
Property Plant And Equipment [Line Items]
Total property and equipment, gross	12,941	12,824
Construction in progress
Property Plant And Equipment [Line Items]
Total property and equipment, gross	$ 9,039	$ 5,882