Business And Geographic Segment Information (Additional Product Information For Net Sales) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jan. 29, 2012	Jan. 30, 2011	Jan. 29, 2012	Jan. 30, 2011
Segment Reporting Information [Line Items]
Net sales	$ 2,112	$ 2,127	$ 4,273	$ 4,299
Simple Meals [Member]
Segment Reporting Information [Line Items]
Net sales	1,323	1,335	2,633	2,666
Baked Snacks [Member]
Segment Reporting Information [Line Items]
Net sales	557	566	1,159	1,154
Beverages [Member]
Segment Reporting Information [Line Items]
Net sales	$ 232	$ 226	$ 481	$ 479