STOCK-BASED COMPENSATION AND STOCKHOLDERS' EQUITY - Stock-Based Compensation Expense By Statement Of Operations (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based employee compensation expense	$ 107,638	$ 70,878	$ 44,508
Research and development
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based employee compensation expense	31,641	19,712	12,313
Sales and marketing
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based employee compensation expense	33,869	20,205	11,951
General and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based employee compensation expense	28,933	22,580	14,717
Service | Cost of Sales
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based employee compensation expense	8,811	5,330	3,752
Other revenue | Cost of Sales
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based employee compensation expense	$ 4,384	$ 3,051	$ 1,775