Guarantor And Non-Guarantor Subsidiaries (Schedule Of Consolidated Statement Of Cash Flows) (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Jul. 28, 2012	Jul. 30, 2011
Condensed Financial Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	$ 380,378	$ 242,999
Purchases of short-term investments	0	(38)
Proceeds from maturities and sale of short-term investments	0	1,604
Proceeds from sale of subsidiary	35	0
Purchases of property and equipment	(56,005)	(76,661)
Net cash provided by (used in) investing activities	(55,970)	(75,095)
Payment of principal related to the term loan	(160,000)	(309,897)
Payment of fees related to the term loan	0	(1,090)
Proceeds from term loan	0	198,949
Payment of principal related to capital leases	(1,389)	(1,311)
Common stock repurchases	(70,153)	(10,044)
Proceeds from issuance of common stock	76,472	93,333
Excess tax benefits (detriments) from stock-based compensation	1,338	(81)
Net cash provided by (used in) financing activities	(153,732)	(30,141)
Effect of exchange rate fluctuations on cash and cash equivalents	(4,252)	812
Net increase (decrease) in cash and cash equivalents	166,424	138,575
Cash and cash equivalents, beginning of period	414,202	333,984
Cash and cash equivalents, end of period	580,626	472,559
Brocade Communications Systems, Inc. [Member]
Condensed Financial Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	304,610	135,029
Purchases of short-term investments		0
Proceeds from maturities and sale of short-term investments		0
Proceeds from sale of subsidiary	35
Purchases of property and equipment	(47,341)	(70,389)
Net cash provided by (used in) investing activities	(47,306)	(70,389)
Payment of principal related to the term loan	(160,000)	(309,897)
Payment of fees related to the term loan		(1,090)
Proceeds from term loan		198,949
Payment of principal related to capital leases	(1,389)	(1,311)
Common stock repurchases	(70,153)	(10,044)
Proceeds from issuance of common stock	76,472	93,333
Excess tax benefits (detriments) from stock-based compensation	1,338	(249)
Net cash provided by (used in) financing activities	(153,732)	(30,309)
Effect of exchange rate fluctuations on cash and cash equivalents	0	0
Net increase (decrease) in cash and cash equivalents	103,572	34,331
Cash and cash equivalents, beginning of period	101,366	23,455
Cash and cash equivalents, end of period	204,938	57,786
Subsidiary Guarantors [Member]
Condensed Financial Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	(716)	431
Purchases of short-term investments		(38)
Proceeds from maturities and sale of short-term investments		1,604
Proceeds from sale of subsidiary	0
Purchases of property and equipment	0	(24)
Net cash provided by (used in) investing activities	0	1,542
Payment of principal related to the term loan	0	0
Payment of fees related to the term loan		0
Proceeds from term loan		0
Payment of principal related to capital leases	0	0
Common stock repurchases	0	0
Proceeds from issuance of common stock	0	0
Excess tax benefits (detriments) from stock-based compensation	0	0
Net cash provided by (used in) financing activities	0	0
Effect of exchange rate fluctuations on cash and cash equivalents	0	0
Net increase (decrease) in cash and cash equivalents	(716)	1,973
Cash and cash equivalents, beginning of period	1,528	6,907
Cash and cash equivalents, end of period	812	8,880
Non-Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	76,484	107,539
Purchases of short-term investments		0
Proceeds from maturities and sale of short-term investments		0
Proceeds from sale of subsidiary	0
Purchases of property and equipment	(8,664)	(6,248)
Net cash provided by (used in) investing activities	(8,664)	(6,248)
Payment of principal related to the term loan	0	0
Payment of fees related to the term loan		0
Proceeds from term loan		0
Payment of principal related to capital leases	0	0
Common stock repurchases	0	0
Proceeds from issuance of common stock	0	0
Excess tax benefits (detriments) from stock-based compensation	0	168
Net cash provided by (used in) financing activities	0	168
Effect of exchange rate fluctuations on cash and cash equivalents	(4,252)	812
Net increase (decrease) in cash and cash equivalents	63,568	102,271
Cash and cash equivalents, beginning of period	311,308	303,622
Cash and cash equivalents, end of period	374,876	405,893
Consolidation, Eliminations [Member]
Condensed Financial Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	0	0
Purchases of short-term investments		0
Proceeds from maturities and sale of short-term investments		0
Proceeds from sale of subsidiary	0
Purchases of property and equipment	0	0
Net cash provided by (used in) investing activities	0	0
Payment of principal related to the term loan	0	0
Payment of fees related to the term loan		0
Proceeds from term loan		0
Payment of principal related to capital leases	0	0
Common stock repurchases	0	0
Proceeds from issuance of common stock	0	0
Excess tax benefits (detriments) from stock-based compensation	0	0
Net cash provided by (used in) financing activities	0	0
Effect of exchange rate fluctuations on cash and cash equivalents	0	0
Net increase (decrease) in cash and cash equivalents	0	0
Cash and cash equivalents, beginning of period	0	0
Cash and cash equivalents, end of period	$ 0	$ 0