Business And Geographic Segment Information (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Jul. 29, 2018	Apr. 29, 2018	Jan. 28, 2018	Oct. 29, 2017	Jul. 30, 2017	Apr. 30, 2017	Jan. 29, 2017	Oct. 30, 2016	Jul. 29, 2018	Jul. 30, 2017	Jul. 31, 2016
Segment Reporting Information [Line Items]
Net sales	$ 2,219	$ 2,125	$ 2,180	$ 2,161	$ 1,664	$ 1,853	$ 2,171	$ 2,202	$ 8,685	$ 7,890	$ 7,961
Sales Revenue, Net [Member] | Customer Concentration Risk [Member] | Wal-Mart Stores, Inc. [Member]
Segment Reporting Information [Line Items]
Concentration Risk, Percentage									18.00%	20.00%	20.00%
International and Campbell Fresh [Member]
Segment Reporting Information [Line Items]
Net sales									$ 2,100