Stock-Based Compensation - Stock-Based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jan. 31, 2022	Jan. 31, 2021	Jan. 31, 2022	Jan. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	$ 31,361	$ 6,589	$ 77,813	$ 14,270
Cost of revenue | Subscription
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	2,639	214	5,824	557
Cost of revenue | Professional services
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	704	164	1,991	301
Sales and marketing
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	8,850	2,790	28,540	5,835
Research and development
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	12,846	846	25,860	1,952
General and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	$ 6,322	$ 2,575	$ 15,598	$ 5,625