Document and Entity Information	6 Months Ended
	Sep. 30, 2013	Oct. 23, 2013
Document Information [Line Items]
Entity Registrant Name	NETSCOUT SYSTEMS INC
Entity Central Index Key	0001078075
Current Fiscal Year End Date	--03-31
Entity Filer Category	Large Accelerated Filer
Document Type	10-Q
Document Period End Date	Sep. 30, 2013
Document Fiscal Year Focus	2014
Document Fiscal Period Focus	Q2
Trading Symbol	NTCT
Amendment Flag	false
Entity Common Stock, Shares Outstanding		41,530,579