Income Taxes - Schedule of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Jan. 31, 2016	Jan. 31, 2015
Deferred tax assets:
Net operating loss carryforwards	$ 137,456	$ 101,815
Tax credit carryover	12,406	6,136
Accruals and reserves	1,921	729
Deferred revenue	20,314	3,538
Stock-based compensation expense	12,588	4,258
Depreciation and amortization	3,397	2,054
Charitable contribution carryforwards	4,380	0
Total deferred tax assets	192,462	118,530
Deferred tax liabilities:
Deferred commissions	(11,000)	(5,924)
Total deferred tax liabilities	(11,000)	(5,924)
Valuation allowance	(180,926)	(112,906)
Net deferred tax (liabilities), net of valuation allowance		$ (300)
Net deferred tax assets, net of valuation allowance	$ 536