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Equity Incentive Plans - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions		3 Months Ended
	Mar. 15, 2020	Apr. 30, 2020	Apr. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant date fair value, options granted in period (in usd per share)		$ 0	$ 5.38
Fair value of options vested during period		$ 7.6	$ 5.9
Unrecognized stock based compensation expense		$ 37.6
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Recognition period, unrecognized stock based compensation expense		2 years 3 months 18 days
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Recognition period, unrecognized stock based compensation expense		2 years 6 months
Unrecognized compensation expense		$ 134.4
Weighted average grant date fair value, stock units granted (in usd per share)		$ 22.48
ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Recognition period, unrecognized stock based compensation expense		4 months 24 days
Unrecognized compensation expense		$ 2.1
Weighted average grant date fair value, stock units granted (in usd per share)	$ 5.48
Performance Based Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant date fair value, stock units granted (in usd per share)		$ 22.30