Equity Incentive Plans - Summary of Stock Option Activity (Details) - USD ($)
$ / shares in Units, $ in Thousands
 9 Months Ended 12 Months Ended
Jan. 31, 2022
Jan. 31, 2021
Apr. 30, 2021
Number of Stock Options Outstanding      
Balance as of April 30, 2020 (in shares) 7,611,016    
Stock options granted (in shares) 175,733    
Stock options exercised (in shares) (2,004,188)    
Stock options cancelled (in shares) (358,624)    
Stock options assumed in acquisition cancelled (in shares) (900)    
Balance as of October 31, 2020 (in shares) 5,486,883   7,611,016
Stock options assumed in acquisition (in shares) $ 10.20    
Stock options assumed in acquisition (in shares) 63,846    
Exercisable as of October 31, 2020 (in shares) 4,148,435    
Weighted- Average Exercise Price      
Balance as of April 30, 2021 (in dollars per share) $ 20.34    
Stock options exercised (in dollars per share) 13.70    
Stock options cancelled (in dollars per share) 31.70    
Balance as of April 30, 2021 (in dollars per share) 25.37   $ 20.34
Exercisable as of July 31, 2020 (in dollars per share) $ 17.51    
Remaining Contractual Term (in years)      
Remaining contract term 6 years 10 days   6 years 7 months 28 days
Exercisable, remaining contractual term 5 years 7 months 28 days    
Aggregate Intrinsic Value      
Balance as of April 30, 2020 $ 768,517    
Balance as of October 31, 2020 387,598   $ 768,517
Exercisable as of October 31, 2020 $ 316,800    
Stock options assumed in acquisition (in shares) 63,846    
Stock options assumed in acquisition (in shares) $ 10.20    
Stock options granted (in shares) 175,733    
Stock options granted (in dollars per share) $ 128.31    
Share Based Compensation Arrangement By Share Based Payment Award Options Assumed In Acquisition Forfeitures And Expirations In Period 900    
Stock options assumed in acquisition cancelled (in dollars per share)   $ 39.68