Balance Sheet Components - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 31, 2017	Oct. 31, 2016	Oct. 31, 2017	Oct. 31, 2016
Balance Sheet Components Disclosure [Abstract]
Depreciation and amortization	$ 15,200	$ 13,200	$ 44,400	$ 34,900
Intangible assets amortization expense	$ 376	$ 376	$ 1,100	$ 1,000
Finite-Lived Intangible Assets [Line Items]
Weighted-average remaining useful life			3 years 7 months 6 days