Fair Value (Fair Value On A Nonrecurring Basis) (Detail) (Fair Value, Inputs, Level 3 [Member], USD $) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended
	Apr. 27, 2013	Apr. 26, 2014	Apr. 27, 2013
Fair Value, Assets and Liabilities Measured on Nonrecurring Basis [Line Items]
Gains (Losses) for the Period	$ 73		$ 55
Property Held For Sale [Member] | Net Carrying Value
Fair Value, Assets and Liabilities Measured on Nonrecurring Basis [Line Items]
Assets Held For Sale	72		72
Property Held For Sale [Member] | Fair Value measurement Nonrecurring Basis Change In Unrealized Gain Loss Included In G&A [Member]
Fair Value, Assets and Liabilities Measured on Nonrecurring Basis [Line Items]
Gains (Losses) for the Period	44		44
Investments In Privately Held Companies
Fair Value, Assets and Liabilities Measured on Nonrecurring Basis [Line Items]
Investment in privately held companies	66		66
Investments In Privately Held Companies | Gains or Losses Included In Other Income (Loss), Net
Fair Value, Assets and Liabilities Measured on Nonrecurring Basis [Line Items]
Gains (Losses) for the Period	(5)	(10)	(23)
Assets No Longer Held At Period End [Member] | Fair Value measurement Nonrecurring Basis Change In Unrealized Gain Loss Included In G&A [Member]
Fair Value, Assets and Liabilities Measured on Nonrecurring Basis [Line Items]
Gains (Losses) for the Period	$ 34		$ 34