Fair Value (Fair Value On Nonrecurring Basis) (Details) (Fair Value, Measurements, Nonrecurring, USD $) In Millions, unless otherwise specified	12 Months Ended
	Jul. 26, 2014	Jul. 27, 2013	Jul. 28, 2012
Fair Value Assets And Liabilities Measured On Nonrecurring Basis [Line Items]
Total Gains (Losses) for the Year Ended	$ (23)	$ 43	$ (434)
Assets held for sale
Fair Value Assets And Liabilities Measured On Nonrecurring Basis [Line Items]
Assets held for sale	0	1	63
Assets held for sale | General and administrative
Fair Value Assets And Liabilities Measured On Nonrecurring Basis [Line Items]
Total Gains (Losses) for the Year Ended	0	(1)	(413)
Investments in privately held companies (impaired)
Fair Value Assets And Liabilities Measured On Nonrecurring Basis [Line Items]
Assets held for sale	28	63	47
Investments in privately held companies (impaired) | Other income (loss), net
Fair Value Assets And Liabilities Measured On Nonrecurring Basis [Line Items]
Total Gains (Losses) for the Year Ended	(21)	(31)	(23)
Purchased intangible assets
Fair Value Assets And Liabilities Measured On Nonrecurring Basis [Line Items]
Assets held for sale	0	0	0
Purchased intangible assets | Cost of Sales and Operating Expenses [Member]
Fair Value Assets And Liabilities Measured On Nonrecurring Basis [Line Items]
Total Gains (Losses) for the Year Ended	0	0	(12)
Gains (losses) on assets no longer held at end of fiscal year
Fair Value Assets And Liabilities Measured On Nonrecurring Basis [Line Items]
Total Gains (Losses) for the Year Ended	$ (2)	$ 75	$ 14