Divestitures (Schedule of Results of Operations of Discontinued Operations) (Details) - USD ($) $ in Millions	3 Months Ended
Oct. 27, 2019	Oct. 28, 2018
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Earnings (loss) from discontinued operations	$ (3)	$ 14
Campbell Fresh [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net sales		226
Discontinued Operations, Impairment charges		14
Disposal Group, Including Discontinued Operation, Operating Income (Loss)		(12)
Discontinued Operation, Tax Effect of Discontinued Operation		(3)
Discontinued Operation, Gain (Loss) from Disposal of Discontinued Operation, before Income Tax		(1)
Discontinued Operation, Tax Effect of Gain (Loss) from Disposal of Discontinued Operation		0
Earnings (loss) from discontinued operations		(10)
Campbell International [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net sales	223	266
Discontinued Operations, Impairment charges	0	0
Disposal Group, Including Discontinued Operation, Operating Income (Loss)	37	35
Discontinued Operation, Tax Effect of Discontinued Operation	13	10
Discontinued Operation, Gain (Loss) from Disposal of Discontinued Operation, before Income Tax	(51)	(1)
Discontinued Operation, Tax Effect of Gain (Loss) from Disposal of Discontinued Operation	(24)	0
Earnings (loss) from discontinued operations	$ (3)	$ 24

Amount before tax of gain (loss) not previously recognized resulting from the disposal of a discontinued operation.

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