Accumulated Other Comprehensive Income (Loss) (Schecule of amounts reclassified from AOCI) (Details) - USD ($) $ in Millions	3 Months Ended
	Oct. 29, 2017	Oct. 30, 2016
Accumulated Other Comprehensive Income (Loss) [Line Items]
Cost of products sold	$ 1,378	$ 1,351
Interest expense	31	29
Other expenses / (income)	(29)	11
Earnings before taxes	(382)	(429)
Taxes on earnings	107	137
Net earnings attributable to Campbell Soup Company	(275)	(292)
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Earnings before taxes	(2)	2
Taxes on earnings	0	0
Net earnings attributable to Campbell Soup Company	(2)	2
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member] | Foreign Exchange Contract [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Cost of products sold	(2)	1
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member] | Interest Rate Contract [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Interest expense	0	1
Accumulated Defined Benefit Plans Adjustment, Net Prior Service [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other expenses / (income)	(7)	(6)
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Taxes on earnings	2	2
Net earnings attributable to Campbell Soup Company	$ (5)	$ (4)