Guarantor And Non-Guarantor Subsidiaries (Schedule Of Consolidated Balance Sheet) (Details) (USD $) In Thousands, unless otherwise specified	Jul. 28, 2012	Oct. 29, 2011
Condensed Financial Statements, Captions [Line Items]
Cash, cash equivalents and short-term investments	$ 581,434	$ 414,976
Accounts receivable, net	231,155	249,141
Inventories	74,200	74,172
Intercompany receivables	0	0
Other current assets	104,576	105,912
Total current assets	991,365	844,201
Property and equipment, net	523,405	532,384
Investment in subsidiaries	0	0
Other non-current assets	1,982,754	2,097,723
Total assets	3,497,524	3,474,308
Accounts payable	116,469	109,471
Current portion of long-term debt	8,515	40,539
Intercompany payables	0	0
Other current liabilities	430,384	415,977
Total current liabilities	555,368	565,987
Total long-term debt, net of current portion	621,206	748,904
Other non-current liabilities	129,349	145,279
Total liabilities	1,305,923	1,460,170
Total stockholders' equity	2,191,601	2,014,138
Total liabilities and stockholders' equity	3,497,524	3,474,308
Brocade Communications Systems, Inc. [Member]
Condensed Financial Statements, Captions [Line Items]
Cash, cash equivalents and short-term investments	204,938	101,367
Accounts receivable, net	149,061	157,839
Inventories	63,751	50,000
Intercompany receivables	0	0
Other current assets	91,810	87,495
Total current assets	509,560	396,701
Property and equipment, net	450,454	460,347
Investment in subsidiaries	1,284,970	1,285,356
Other non-current assets	1,471,483	1,506,086
Total assets	3,716,467	3,648,490
Accounts payable	91,883	85,700
Current portion of long-term debt	8,515	40,539
Intercompany payables	423,467	377,228
Other current liabilities	290,665	276,982
Total current liabilities	814,530	780,449
Total long-term debt, net of current portion	621,206	748,904
Other non-current liabilities	89,130	104,999
Total liabilities	1,524,866	1,634,352
Total stockholders' equity	2,191,601	2,014,138
Total liabilities and stockholders' equity	3,716,467	3,648,490
Subsidiary Guarantors [Member]
Condensed Financial Statements, Captions [Line Items]
Cash, cash equivalents and short-term investments	1,620	2,301
Accounts receivable, net	(1,554)	(2,149)
Inventories	0	0
Intercompany receivables	465,891	446,455
Other current assets	664	805
Total current assets	466,621	447,412
Property and equipment, net	54,206	55,594
Investment in subsidiaries	0	0
Other non-current assets	510,021	590,318
Total assets	1,030,848	1,093,324
Accounts payable	353	376
Current portion of long-term debt	0	0
Intercompany payables	0	0
Other current liabilities	12,758	17,261
Total current liabilities	13,111	17,637
Total long-term debt, net of current portion	0	0
Other non-current liabilities	43	580
Total liabilities	13,154	18,217
Total stockholders' equity	1,017,694	1,075,107
Total liabilities and stockholders' equity	1,030,848	1,093,324
Non-Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Cash, cash equivalents and short-term investments	374,876	311,308
Accounts receivable, net	83,648	93,451
Inventories	10,449	24,172
Intercompany receivables	0	0
Other current assets	11,545	15,609
Total current assets	480,518	444,540
Property and equipment, net	18,745	16,443
Investment in subsidiaries	0	0
Other non-current assets	1,250	1,319
Total assets	500,513	462,302
Accounts payable	24,233	23,395
Current portion of long-term debt	0	0
Intercompany payables	42,424	69,227
Other current liabilities	126,404	119,731
Total current liabilities	193,061	212,353
Total long-term debt, net of current portion	0	0
Other non-current liabilities	40,176	39,700
Total liabilities	233,237	252,053
Total stockholders' equity	267,276	210,249
Total liabilities and stockholders' equity	500,513	462,302
Consolidating Adjustments [Member]
Condensed Financial Statements, Captions [Line Items]
Cash, cash equivalents and short-term investments	0	0
Accounts receivable, net	0	0
Inventories	0	0
Intercompany receivables	(465,891)	(446,455)
Other current assets	557	2,003
Total current assets	(465,334)	(444,452)
Property and equipment, net	0	0
Investment in subsidiaries	(1,284,970)	(1,285,356)
Other non-current assets	0	0
Total assets	(1,750,304)	(1,729,808)
Accounts payable	0	0
Current portion of long-term debt	0	0
Intercompany payables	(465,891)	(446,455)
Other current liabilities	557	2,003
Total current liabilities	(465,334)	(444,452)
Total long-term debt, net of current portion	0	0
Other non-current liabilities	0	0
Total liabilities	(465,334)	(444,452)
Total stockholders' equity	(1,284,970)	(1,285,356)
Total liabilities and stockholders' equity	$ (1,750,304)	$ (1,729,808)