Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended
	Nov. 01, 2020	Oct. 27, 2019
Statement of Comprehensive Income [Abstract]
Net earnings	$ 309	$ 166
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, before Tax [Abstract]
Foreign currency translation adjustments, before tax	0	(4)
Reclassification of currency translation adjustments realized upon disposal of business, before tax	0	82
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification, before Tax [Abstract]
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax	(1)	0
Reclassification adjustment for (gains) losses included in net earnings, before tax	0	2
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Adjustment, before Tax, [Abstract]
Reclassification of prior service credit included in net earnings, before tax	(1)	(7)
Other comprehensive income (loss), before tax	(2)	73
Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Tax [Abstract]
Foreign currency translation adjustments, tax (expense) benefit	0	0
Reclassification of currency translation adjustments realized upon disposal of business, tax (expense) benefit	0	0
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification, Tax [Abstract]
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Tax	1	0
Reclassification adjustment for (gains) losses included in net earnings, tax (expense) benefit	0	(1)
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, Tax [Abstract]
Reclassification of prior service credit included in net earnings, tax (expense) benefit	0	1
Other comprehensive income (loss), tax (expense) benefit	1	0
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax [Abstract]
Foreign currency translation adjustments, after-tax	0	(4)
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Reclassification Adjustment from AOCI, Realized upon Sale or Liquidation, Net of Tax	0	82
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification and Tax [Abstract]
Unrealized gains (losses) arising during the period, after-tax	0	0
Reclassification adjustment for (gains) losses included in net earnings, after-tax	0	1
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax [Abstract]
Reclassification of prior service credit included in net earnings, after-tax	(1)	(6)
Other comprehensive income (loss), after tax	(1)	73
Total comprehensive income (loss), after-tax	308	239
Total comprehensive income (loss) attributable to noncontrolling interests	(2)	1
Total comprehensive income (loss) attributable to Campbell Soup Company	$ 310	$ 238