Guarantor And Non-Guarantor Subsidiaries (Schedule Of Consolidated Balance Sheet) (Details) (USD $) In Thousands, unless otherwise specified	Apr. 28, 2012	Oct. 29, 2011
Condensed Financial Statements, Captions [Line Items]
Cash, cash equivalents and short-term investments	$ 545,136	$ 414,976
Accounts receivable, net	217,837	249,141
Inventories	81,551	74,172
Intercompany receivables	0	0
Other current assets	114,291	105,912
Total current assets	958,815	844,201
Property and equipment, net	527,226	532,384
Investment in subsidiaries	0	0
Other non-current assets	2,026,971	2,097,723
Total assets	3,513,012	3,474,308
Accounts payable	102,699	109,471
Current portion of long-term debt	17,330	40,539
Intercompany payables	0	0
Other current liabilities	433,105	415,977
Total current liabilities	553,134	565,987
Total long-term debt, net of current portion	652,365	748,904
Other non-current liabilities	132,087	145,279
Total liabilities	1,337,586	1,460,170
Total stockholders' equity	2,175,426	2,014,138
Total liabilities and stockholders' equity	3,513,012	3,474,308
Brocade Communications Systems, Inc. [Member]
Condensed Financial Statements, Captions [Line Items]
Cash, cash equivalents and short-term investments	186,562	101,367
Accounts receivable, net	146,108	157,839
Inventories	59,350	50,000
Intercompany receivables	0	0
Other current assets	100,360	87,495
Total current assets	492,380	396,701
Property and equipment, net	454,602	460,347
Investment in subsidiaries	1,283,055	1,285,356
Other non-current assets	1,490,192	1,506,086
Total assets	3,720,229	3,648,490
Accounts payable	85,280	85,700
Current portion of long-term debt	17,330	40,539
Intercompany payables	406,451	377,228
Other current liabilities	292,135	276,982
Total current liabilities	801,196	780,449
Total long-term debt, net of current portion	652,365	748,904
Other non-current liabilities	91,242	104,999
Total liabilities	1,544,803	1,634,352
Total stockholders' equity	2,175,426	2,014,138
Total liabilities and stockholders' equity	3,720,229	3,648,490
Subsidiary Guarantors [Member]
Condensed Financial Statements, Captions [Line Items]
Cash, cash equivalents and short-term investments	3,585	2,301
Accounts receivable, net	(1,696)	(2,149)
Inventories	0	0
Intercompany receivables	453,449	446,455
Other current assets	696	805
Total current assets	456,034	447,412
Property and equipment, net	54,667	55,594
Investment in subsidiaries	0	0
Other non-current assets	535,525	590,318
Total assets	1,046,226	1,093,324
Accounts payable	363	376
Current portion of long-term debt	0	0
Intercompany payables	0	0
Other current liabilities	13,823	17,261
Total current liabilities	14,186	17,637
Total long-term debt, net of current portion	0	0
Other non-current liabilities	216	580
Total liabilities	14,402	18,217
Total stockholders' equity	1,031,824	1,075,107
Total liabilities and stockholders' equity	1,046,226	1,093,324
Non-Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Cash, cash equivalents and short-term investments	354,989	311,308
Accounts receivable, net	73,425	93,451
Inventories	22,201	24,172
Intercompany receivables	0	0
Other current assets	11,529	15,609
Total current assets	462,144	444,540
Property and equipment, net	17,957	16,443
Investment in subsidiaries	0	0
Other non-current assets	1,254	1,319
Total assets	481,355	462,302
Accounts payable	17,056	23,395
Current portion of long-term debt	0	0
Intercompany payables	46,998	69,227
Other current liabilities	125,441	119,731
Total current liabilities	189,495	212,353
Total long-term debt, net of current portion	0	0
Other non-current liabilities	40,629	39,700
Total liabilities	230,124	252,053
Total stockholders' equity	251,231	210,249
Total liabilities and stockholders' equity	481,355	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	(453,449)	(446,455)
Other current assets	1,706	2,003
Total current assets	(451,743)	(444,452)
Property and equipment, net	0	0
Investment in subsidiaries	(1,283,055)	(1,285,356)
Other non-current assets	0	0
Total assets	(1,734,798)	(1,729,808)
Accounts payable	0	0
Current portion of long-term debt	0	0
Intercompany payables	(453,449)	(446,455)
Other current liabilities	1,706	2,003
Total current liabilities	(451,743)	(444,452)
Total long-term debt, net of current portion	0	0
Other non-current liabilities	0	0
Total liabilities	(451,743)	(444,452)
Total stockholders' equity	(1,283,055)	(1,285,356)
Total liabilities and stockholders' equity	$ (1,734,798)	$ (1,729,808)