Net Loss Per Share - Schedule of Basic and Diluted Earnings (Loss) Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Apr. 30, 2020	Apr. 30, 2019
Numerator:
Net loss	$ (53,967)	$ (33,240)
Denominator:
Weighted-average shares used to compute net loss per share, basic and diluted (in shares)	57,649,524	54,710,746
Net loss per share, basic and diluted (in dollars per share)	$ (0.94)	$ (0.61)