Document And Entity Information	9 Months Ended
	Jul. 28, 2012	Aug. 24, 2012
Entity Information [Line Items]
Entity Registrant Name	BROCADE COMMUNICATIONS SYSTEMS INC
Entity Central Index Key	0001009626
Current Fiscal Year End Date	--10-27
Entity Filer Category	Large Accelerated Filer
Document Type	10-Q
Document Period End Date	Jul. 28, 2012
Document Fiscal Year Focus	2012
Document Fiscal Period Focus	Q3
Amendment Flag	false
Entity Common Stock, Shares Outstanding		458,695,877