Segment Information and Major Customers (Summary Of Reportable Segments) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Oct. 25, 2014	Oct. 26, 2013
Segment Reporting Information [Line Items]
Revenue	$ 12,245	$ 12,085
Gross margin	7,333	7,407
Unallocated corporate items
Segment Reporting Information [Line Items]
Gross margin	(417)	(210)
Americas
Segment Reporting Information [Line Items]
Revenue	7,501	7,316
Gross margin	4,810	4,650
EMEA
Segment Reporting Information [Line Items]
Revenue	3,002	2,933
Gross margin	1,915	1,888
APJC
Segment Reporting Information [Line Items]
Revenue	1,742	1,836
Gross margin	1,025	1,079
Segment total
Segment Reporting Information [Line Items]
Gross margin	$ 7,750	$ 7,617