Business And Geographic Segment Information Business And Geographic Segment Information Business And Geographic Segment Information (Geographic Information, Net Sales) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended								12 Months Ended
	Aug. 03, 2014	Apr. 27, 2014	Jan. 26, 2014	Oct. 27, 2013	Jul. 28, 2013	Apr. 28, 2013	Jan. 27, 2013	Oct. 28, 2012	Aug. 03, 2014	Jul. 28, 2013	Jul. 29, 2012
Segment Reporting Information [Line Items]
Net sales	$ 1,852	$ 1,970	$ 2,281	$ 2,165	$ 1,723	$ 1,962	$ 2,162	$ 2,205	$ 8,268	$ 8,052	$ 7,175
UNITED STATES
Segment Reporting Information [Line Items]
Net sales									6,432	6,195	5,359
AUSTRALIA
Segment Reporting Information [Line Items]
Net sales									709	801	819
Other Countries [Member]
Segment Reporting Information [Line Items]
Net sales									$ 1,127	$ 1,056	$ 997