Income Taxes - Schedule of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Jan. 31, 2018	Jan. 31, 2017
Deferred tax assets:
Net operating loss carryforwards	$ 123,013	$ 98,587
Stock-based compensation	7,926	3,611
Deferred revenue	1,391	4,497
Other reserves and accruals	3,084	3,768
Credits	791	625
Total deferred tax assets	136,205	111,088
Valuation allowance	(125,874)	(98,379)
Total deferred tax assets, net	10,331	12,709
Deferred tax liabilities:
Deferred commissions	(6,849)	(8,802)
Capitalized internal-use software costs	(2,389)	(2,816)
Goodwill	(175)	(196)
Depreciation and amortization	(441)	(953)
Total deferred tax liabilities	(9,854)	(12,767)
Net deferred tax asset	$ 477
Net deferred tax liabilities		$ (58)