Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	12 Months Ended
	Jul. 29, 2018	Jul. 30, 2017	Jul. 31, 2016
Statement of Comprehensive Income [Abstract]
Net earnings	$ 261	$ 887	$ 563
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, before Tax [Abstract]
Foreign currency translation adjustments, before tax	(69)	40	45
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, before Tax [Abstract]
Unrealized gains (losses) arising during period, before Tax	23	19	(45)
Reclassification adjustment for (gains) losses included in net earnings, before tax	3	11	(9)
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Adjustment, before Tax, [Abstract]
Prior service credit arising during the period, before tax	9	12	93
Reclassification of prior service credit included in net earnings, before tax	(27)	(25)	(1)
Other comprehensive income (loss), before tax	(61)	57	83
Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Tax [Abstract]
Foreign currency translation adjustments, tax (expense) benefit	0	0	0
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Tax Effect [Abstract]
Unrealized gains (losses) arising during the period, tax (expense) benefit	(7)	(7)	16
Reclassification adjustment for (gains) losses included in net earnings, tax (expense) benefit	(1)	(4)	2
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, Tax [Abstract]
Prior service credit arising during the period, tax	(2)	(4)	(34)
Reclassification of prior service credit included in net earnings, tax (expense) benefit	7	9	0
Other comprehensive income (loss), tax (expense) benefit	(3)	(6)	(16)
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax [Abstract]
Foreign currency translation adjustments, after-tax	(69)	40	45
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax [Abstract]
Unrealized gains (losses) arising during the period, after-tax	16	12	(29)
Reclassification adjustment for (gains) losses included in net earnings, after-tax	2	7	(7)
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax [Abstract]
Prior service credit arising during the period, net of tax	7	8	59
Reclassification of prior service credit included in net earnings, after-tax	(20)	(16)	(1)
Other comprehensive income (loss), after tax	(64)	51	67
Total comprehensive income (loss), after-tax	197	938	630
Total comprehensive income (loss) attributable to noncontrolling interests	1	0	3
Total comprehensive income (loss) attributable to Campbell Soup Company	$ 196	$ 938	$ 627