Document and Entity Information - shares	3 Months Ended
	Oct. 31, 2015	Dec. 04, 2015
Document Information [Line Items]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Oct. 31, 2015
Document Fiscal Year Focus	2016
Document Fiscal Period Focus	Q1
Trading Symbol	SCMR
Entity Registrant Name	SYCAMORE NETWORKS INC
Entity Central Index Key	0001092367
Current Fiscal Year End Date	--07-31
Entity Filer Category	Smaller Reporting Company
Entity Common Stock, Shares Outstanding		28,882,093