Segment Information And Major Customers - Additional Information (Detail) (USD $)	12 Months Ended
	Jul. 28, 2012 Customer	Jul. 30, 2011 Customer	Jul. 31, 2010 Customer
Segment Reporting Information [Line Items]
Number of geographic segments	three	four
Net sales	$ 46,061,000,000	$ 43,218,000,000	$ 40,040,000,000
Number of customer accounted for 10% or more net sales	0	0	0
Federal
Segment Reporting Information [Line Items]
Net sales	22,600,000,000	21,500,000,000	20,400,000,000
International
Segment Reporting Information [Line Items]
Cash and cash equivalents and investments	42,500,000,000	39,800,000,000
United States
Segment Reporting Information [Line Items]
Cash and cash equivalents and investments	$ 6,200,000,000	$ 4,800,000,000