Guarantor And Non-Guarantor Subsidiaries (Schedule Of Condensed Consolidated Statement Of Cash Flows) (Details) (USD $) In Thousands	9 Months Ended
	Jul. 30, 2011	Jul. 31, 2010
Net cash provided by (used in) operating activities	$ 242,999	$ 192,090
Purchases of short-term investments	(38)	(41)
Proceeds from maturities and sale of short-term investments	1,604	1,788
Proceeds from sale of property		30,185
Purchases of property and equipment	(76,661)	(155,970)
Net cash provided by (used in) investing activities	(75,095)	(124,038)
Payment of debt issuance fees related to the Senior Secured Notes		(3,665)
Payment of principal related to the revolving credit facility		(14,050)
Payment of principal related to the convertible subordinated debt		(172,500)
Payment of principal related to the term loan	(309,897)	(552,808)
Payment of fees related to the term loan	(1,090)
Proceeds from term loan	198,949
Common stock repurchases	(10,044)	(25,004)
Payment of principal related to capital leases	(1,311)	(494)
Proceeds from Senior Secured Notes		587,968
Proceeds from issuance of common stock, net	93,333	69,883
Excess tax benefits or detriments from stock-based compensation	(81)	5,318
Net cash provided by (used in) financing activities	(30,141)	(105,352)
Effect of exchange rate fluctuations on cash and cash equivalents	812	(4,356)
Net increase (decrease) in cash and cash equivalents	138,575	(41,656)
Cash and cash equivalents, beginning of period	333,984	334,193
Cash and cash equivalents, end of period	472,559	292,537
Brocade Communications Systems, Inc. [Member]
Net cash provided by (used in) operating activities	135,029	(15,055)
Proceeds from sale of property		30,185
Purchases of property and equipment	(70,389)	(151,662)
Net cash provided by (used in) investing activities	(70,389)	(121,477)
Payment of debt issuance fees related to the Senior Secured Notes		(3,665)
Payment of principal related to the revolving credit facility		(14,050)
Payment of principal related to the term loan	(309,897)	(552,808)
Payment of fees related to the term loan	(1,090)
Proceeds from term loan	198,949
Common stock repurchases	(10,044)	(25,004)
Payment of principal related to capital leases	(1,311)	(494)
Proceeds from Senior Secured Notes		587,968
Proceeds from issuance of common stock, net	93,333	69,883
Excess tax benefits or detriments from stock-based compensation	(249)	5,318
Net cash provided by (used in) financing activities	(30,309)	67,148
Net increase (decrease) in cash and cash equivalents	34,331	(69,384)
Cash and cash equivalents, beginning of period	23,455	74,509
Cash and cash equivalents, end of period	57,786	5,125
Subsidiary Guarantors [Member]
Net cash provided by (used in) operating activities	431	168,697
Purchases of short-term investments	(38)	(41)
Proceeds from maturities and sale of short-term investments	1,604	1,788
Purchases of property and equipment	(24)	372
Net cash provided by (used in) investing activities	1,542	2,119
Payment of principal related to the convertible subordinated debt		(172,500)
Net cash provided by (used in) financing activities		(172,500)
Net increase (decrease) in cash and cash equivalents	1,973	(1,684)
Cash and cash equivalents, beginning of period	6,907	5,748
Cash and cash equivalents, end of period	8,880	4,064
Foreign Non-Guarantor Subsidiaries [Member]
Net cash provided by (used in) operating activities	107,539	38,448
Purchases of property and equipment	(6,248)	(4,680)
Net cash provided by (used in) investing activities	(6,248)	(4,680)
Excess tax benefits or detriments from stock-based compensation	168
Net cash provided by (used in) financing activities	168
Effect of exchange rate fluctuations on cash and cash equivalents	812	(4,356)
Net increase (decrease) in cash and cash equivalents	102,271	29,412
Cash and cash equivalents, beginning of period	303,622	253,936
Cash and cash equivalents, end of period	$ 405,893	$ 283,348