Goodwill And Purchased Intangible Assets (Schedule Of Amortization Of Purchased Intangible Assets) (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jan. 25, 2014	Jan. 26, 2013	Jan. 25, 2014	Jan. 26, 2013
Acquired Finite-Lived Intangible Assets [Line Items]
Amortization of Purchased Intangible Assets	$ 71	$ 118	$ 136	$ 240
Cost of Sales
Acquired Finite-Lived Intangible Assets [Line Items]
Amortization of Purchased Intangible Assets	189	145	363	288
Operating Expenses
Acquired Finite-Lived Intangible Assets [Line Items]
Amortization of Purchased Intangible Assets	71	118	136	240
Cost of Sales and Operating Expenses [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Amortization of Purchased Intangible Assets	$ 260	$ 263	$ 499	$ 528