Guarantor And Non-Guarantor Subsidiaries (Schedule Of Consolidated Balance Sheet) (Details) (USD $) In Thousands, unless otherwise specified	Oct. 29, 2011	Oct. 30, 2010	Oct. 31, 2009
Cash and cash equivalents and short-term investments	$ 414,976	$ 335,982
Accounts receivable, net	249,141	317,363
Inventories	74,172	76,808
Other current assets	105,912	136,135
Total current assets	844,201	866,288
Property and equipment, net	532,384	539,117	442,408
Other non-current assets	2,097,723	2,240,607
Total assets	3,474,308	3,646,012
Accounts payable	109,471	147,130
Current portion of debt	40,539	30,540
Other current liabilities	415,977	394,436
Total current liabilities	565,987	572,106
Debt, net of current portion	748,904	899,273
Other non-current liabilities	145,279	139,228
Total liabilities	1,460,170	1,610,607
Total stockholders' equity	2,014,138	2,035,405
Total liabilities and stockholders' equity	3,474,308	3,646,012
Brocade Communications Systems, Inc. [Member]
Cash and cash equivalents and short-term investments	101,367	23,455
Accounts receivable, net	157,839	212,541
Inventories	50,000	63,713
Other current assets	87,495	122,192
Total current assets	396,701	421,901
Property and equipment, net	460,347	466,247
Other non-current assets	1,506,086	1,499,774
Total assets	2,363,134	2,387,922
Accounts payable	85,700	128,182
Current portion of debt	40,539	30,540
Intercompany payables	391,278	409,129
Other current liabilities	276,982	258,796
Total current liabilities	794,499	826,647
Debt, net of current portion	748,904	899,273
Other non-current liabilities	104,999	99,679
Total liabilities	1,648,402	1,825,599
Total stockholders' equity	714,732	562,323
Total liabilities and stockholders' equity	2,363,134	2,387,922
Subsidiary Guarantors [Member]
Cash and cash equivalents and short-term investments	2,301	8,905
Accounts receivable, net	(2,149)	1,699
Intercompany receivables	461,717	396,442
Other current assets	805	875
Total current assets	462,674	407,921
Property and equipment, net	55,594	58,040
Other non-current assets	590,318	734,469
Total assets	1,108,586	1,200,430
Accounts payable	376	389
Other current liabilities	17,261	29,752
Total current liabilities	17,637	30,141
Other non-current liabilities	580	3,361
Total liabilities	18,217	33,502
Total stockholders' equity	1,090,369	1,166,928
Total liabilities and stockholders' equity	1,108,586	1,200,430
Foreign Non-Guarantor Subsidiaries [Member]
Cash and cash equivalents and short-term investments	311,308	303,622
Accounts receivable, net	93,451	103,456
Inventories	24,172	13,095
Other current assets	15,609	9,999
Total current assets	444,540	430,172
Property and equipment, net	16,443	14,830
Other non-current assets	1,319	6,364
Total assets	462,302	451,366
Accounts payable	23,395	18,892
Intercompany payables	70,439	(12,687)
Other current liabilities	119,731	102,819
Total current liabilities	213,565	109,024
Other non-current liabilities	39,700	36,188
Total liabilities	253,265	145,212
Total stockholders' equity	209,037	306,154
Total liabilities and stockholders' equity	462,302	451,366
Consolidating Adjustments [Member]
Accounts receivable, net		(333)
Intercompany receivables	(461,717)	(396,442)
Other current assets	2,003	3,069
Total current assets	(459,714)	(393,706)
Total assets	(459,714)	(393,706)
Accounts payable		(333)
Intercompany payables	(461,717)	(396,442)
Other current liabilities	2,003	3,069
Total current liabilities	(459,714)	(393,706)
Total liabilities	(459,714)	(393,706)
Total liabilities and stockholders' equity	$ (459,714)	$ (393,706)