Goodwill And Purchased Intangible Assets - Additional Information (Detail) (USD $)	12 Months Ended
	Jul. 27, 2013	Jul. 28, 2012	Jul. 30, 2011
Finite-Lived Intangible Assets [Line Items]
Impairment of Intangible assets	$ 0	$ 12,000,000	$ 164,000,000
Technology-Based Intangible Assets [Member]
Finite-Lived Intangible Assets [Line Items]
Impairment of Intangible assets		12,000,000	97,000,000
Customer Relationships
Finite-Lived Intangible Assets [Line Items]
Impairment of Intangible assets			40,000,000
Other Intangible Assets [Member]
Finite-Lived Intangible Assets [Line Items]
Impairment of Intangible assets			27,000,000
Cost Of Sales
Finite-Lived Intangible Assets [Line Items]
Impairment of Intangible assets			64,000,000
Intaqngible amortization, operating expense [Member]
Finite-Lived Intangible Assets [Line Items]
Impairment of Intangible assets			92,000,000
Other Restructuring [Member]
Finite-Lived Intangible Assets [Line Items]
Impairment of Intangible assets			$ 8,000,000