Employee Stock Plans - Stock-Based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Apr. 30, 2020	Apr. 30, 2019
Cost of Revenue
Stock-based compensation expense	$ 10,884	$ 7,959
Cost of subscription revenue
Cost of Revenue
Stock-based compensation expense	852	493
Cost of professional services revenue
Cost of Revenue
Stock-based compensation expense	1,650	1,359
Research and development
Cost of Revenue
Stock-based compensation expense	3,542	3,191
Sales and marketing
Cost of Revenue
Stock-based compensation expense	3,005	1,852
General and administrative
Cost of Revenue
Stock-based compensation expense	$ 1,835	$ 1,064