Net Loss Per Share - Schedule of the Calculation of Basic and Diluted Net Loss Per Share Attributable to Common Stockholders (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Apr. 30, 2020	Apr. 30, 2019
Numerator:
Net loss	$ (58,014)	$ (103,130)
Denominator:
Weighted-average shares used in computing net loss, per share basic and diluted (in shares)	295,293	271,352
Net loss per share, basic and diluted (in shares)	$ (0.20)	$ (0.38)