Document and Entity Information	3 Months Ended
Sep. 30, 2011	Nov. 09, 2011
Document Information [Line Items]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2011
Document Fiscal Year Focus	2012
Document Fiscal Period Focus	Q1
Trading Symbol	NSSC
Entity Registrant Name	NAPCO SECURITY TECHNOLOGIES, INC
Entity Central Index Key	0000069633
Current Fiscal Year End Date	--06-30
Entity Filer Category	Smaller Reporting Company
Entity Common Stock, Shares Outstanding		19,095,713

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