Business Combinations (Summary Of Allocation Of Total Purchase Consideration) (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Jul. 27, 2013	Jul. 28, 2012	Jul. 30, 2011
Business Acquisition [Line Items]
Purchase Consideration	$ 1,977	$ 398	$ 288
Acquired Cash and Cash Equivalents	156
Net Tangible Assets Acquired/ (Liabilities Assumed)	(137)	(39)	(10)
Business Combination, Purchased intangible assets	645	200	114
Goodwill	1,469	237	184
NDS Group Limited [Member]
Business Acquisition [Line Items]
Cash consideration to seller	4,012
Repayments of Assumed Debt	993
Purchase Consideration	5,005
Acquired Cash and Cash Equivalents	98
Accounts receivable, net	199
Other tangible assets	268
Business Combination, Purchased intangible assets	1,746
Goodwill	3,444
Deferred Tax Liabilities, Net	(378)
Liabilities assumed	(372)
Meraki Inc [Member]
Business Acquisition [Line Items]
Purchase Consideration	974
Net Tangible Assets Acquired/ (Liabilities Assumed)	(59)
Business Combination, Purchased intangible assets	289
Goodwill	744
Intucell Ltd [Member]
Business Acquisition [Line Items]
Purchase Consideration	360
Net Tangible Assets Acquired/ (Liabilities Assumed)	(23)
Business Combination, Purchased intangible assets	106
Goodwill	277
Ubiquisys Ltd [Member]
Business Acquisition [Line Items]
Purchase Consideration	280
Net Tangible Assets Acquired/ (Liabilities Assumed)	(30)
Business Combination, Purchased intangible assets	123
Goodwill	187
All Others [Member]
Business Acquisition [Line Items]
Purchase Consideration	363	159
Net Tangible Assets Acquired/ (Liabilities Assumed)	(25)	(24)
Business Combination, Purchased intangible assets	127	103
Goodwill	261	80
Light Wire [Member]
Business Acquisition [Line Items]
Purchase Consideration		239
Net Tangible Assets Acquired/ (Liabilities Assumed)		(15)
Business Combination, Purchased intangible assets		97
Goodwill		$ 157