Common Stock - Schedule of Total Stock-Based Compensation Expense Recognized (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 31, 2017	Jul. 31, 2016	Jul. 31, 2017	Jul. 31, 2016
Stock-based compensation:
Total stock-based compensation expense	$ 22,453	$ 3,643	$ 25,918	$ 7,441
Cost of Product Revenue
Stock-based compensation:
Total stock-based compensation expense	690	67	761	129
Cost of Support and Maintenance Revenue
Stock-based compensation:
Total stock-based compensation expense	538	96	653	172
Research and development
Stock-based compensation:
Total stock-based compensation expense	8,380	1,384	9,656	2,860
Sales and marketing
Stock-based compensation:
Total stock-based compensation expense	4,638	1,027	5,682	2,250
General and administrative
Stock-based compensation:
Total stock-based compensation expense	$ 8,207	$ 1,069	$ 9,166	$ 2,030