Stock-Based Compensation - Stock-Based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Oct. 31, 2021	Oct. 31, 2020	Oct. 31, 2021	Oct. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	$ 32,540	$ 5,201	$ 46,452	$ 7,681
Cost of revenue | Subscription
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	2,364	159	3,185	343
Cost of revenue | Professional services
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	685	89	1,287	137
Sales and marketing
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	13,555	2,190	19,690	3,045
Research and development
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	10,256	648	13,014	1,106
General and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	$ 5,680	$ 2,115	$ 9,276	$ 3,050