Fair Value (Fair Value On Nonrecurring Basis) (Detail) (Fair Value, Measurements, Nonrecurring, USD $) In Millions, unless otherwise specified	12 Months Ended
	Jul. 27, 2013	Jul. 28, 2012	Jul. 30, 2011
Fair Value Assets And Liabilities Measured On Nonrecurring Basis [Line Items]
Total Gains (Losses) for the Year Ended	$ 43	$ (434)	$ (273)
Net Carrying Value
Fair Value Assets And Liabilities Measured On Nonrecurring Basis [Line Items]
Assets held for sale	1	63	20
Investments in privately held companies	63	47	13
Purchased intangible assets	0	0	0
Manufacturing operations held for sale	0	0	167
Assets Held-for-sale [Member] | Unrealized Gain Loss Included In G&A [Member]
Fair Value Assets And Liabilities Measured On Nonrecurring Basis [Line Items]
Total Gains (Losses) for the Year Ended	(1)	(413)	(38)
Investments In Privately Held Companies | Change in Gains and Losses included in Other Income (Loss), Net
Fair Value Assets And Liabilities Measured On Nonrecurring Basis [Line Items]
Total Gains (Losses) for the Year Ended	(31)	(23)	(10)
Purchased Intangible Assets | Change in Gains and Losses Included In COGS or Expense[Member]
Fair Value Assets And Liabilities Measured On Nonrecurring Basis [Line Items]
Total Gains (Losses) for the Year Ended	0	(12)	(164)
Manufacturing Facility [Member] | Change in Gains or Losses Related to Goodwill [Member]
Fair Value Assets And Liabilities Measured On Nonrecurring Basis [Line Items]
Total Gains (Losses) for the Year Ended	0	0	(61)
Assets No Longer Held At Period End [Member]
Fair Value Assets And Liabilities Measured On Nonrecurring Basis [Line Items]
Total Gains (Losses) for the Year Ended	$ 75	$ 14	$ 0