SHARE-BASED COMPENSATION - Schedule of Share-Based Compensation Cost and Expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Jun. 30, 2025	Jun. 30, 2024
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Share-based compensation expense	$ 19,959	$ 21,198
Cost of product revenue
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Share-based compensation expense	413	431
Cost of service revenue
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Share-based compensation expense	2,747	2,889
Research and development
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Share-based compensation expense	5,532	5,886
Sales and marketing
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Share-based compensation expense	6,889	7,504
General and administrative
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Share-based compensation expense	$ 4,378	$ 4,488

NETSCOUT SYSTEMS INC 10-Q