Divestitures (Schedule of Results of Operations of Discontinued Operations) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Apr. 26, 2020	Apr. 28, 2019	Apr. 26, 2020	Apr. 28, 2019
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Earnings (loss) from discontinued operations	$ 2	$ (39)	$ 1,036	$ (260)
Campbell Fresh [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Revenue		210		666
Discontinued Operations, Impairment charges		0		360
Disposal Group, Including Discontinued Operation, Operating Income (Loss)		7		(361)
Discontinued Operation, Tax Effect of Discontinued Operation		7		(82)
Discontinued Operation, Gain (Loss) from Disposal of Discontinued Operation, before Income Tax		(24)		(31)
Discontinued Operation, Tax Effect of Gain (Loss) from Disposal of Discontinued Operation		23		21
Earnings (loss) from discontinued operations		(47)		(331)
Campbell International [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Revenue		225	359	802
Discontinued Operations, Impairment charges		0	0	0
Disposal Group, Including Discontinued Operation, Operating Income (Loss)		21	53	115
Discontinued Operation, Tax Effect of Discontinued Operation		12	17	39
Discontinued Operation, Gain (Loss) from Disposal of Discontinued Operation, before Income Tax		(2)	1,039	(7)
Discontinued Operation, Tax Effect of Gain (Loss) from Disposal of Discontinued Operation		(1)	39	(2)
Earnings (loss) from discontinued operations		$ 8	$ 1,036	$ 71

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

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