Cover Page - shares	9 Months Ended
	Dec. 31, 2019	Jan. 30, 2020
Cover page.
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Dec. 31, 2019
Document Transition Report	false
Entity File Number	000-26251
Entity Registrant Name	NETSCOUT SYSTEMS, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	04-2837575
Entity Address, Address Line One	310 Littleton Road
Entity Address, City or Town	Westford
Entity Address, State or Province	MA
Entity Address, Postal Zip Code	01886
City Area Code	978
Local Phone Number	614-4000
Title of 12(b) Security	Common Stock, $0.001 par value per share
Trading Symbol	NTCT
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		73,855,221
Entity Central Index Key	0001078075
Current Fiscal Year End Date	--03-31
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q3
Amendment Flag	false