Divestitures (Schedule of Results of Operations of Discontinued Operations) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jan. 26, 2020	Jan. 27, 2019	Jan. 26, 2020	Jan. 27, 2019
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Earnings (loss) from discontinued operations	$ 1,037	$ (235)	$ 1,034	$ (221)
Campbell Fresh [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net sales		230		456
Discontinued Operations, Impairment charges		346		360
Disposal Group, Including Discontinued Operation, Operating Income (Loss)		(356)		(368)
Discontinued Operation, Tax Effect of Discontinued Operation		(87)		(89)
Discontinued Operation, Gain (Loss) from Disposal of Discontinued Operation, before Income Tax		(6)		(7)
Discontinued Operation, Tax Effect of Gain (Loss) from Disposal of Discontinued Operation		(1)		(2)
Earnings (loss) from discontinued operations		(274)		(284)
Campbell International [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net sales	136	311	359	577
Discontinued Operations, Impairment charges	0	0	0	0
Disposal Group, Including Discontinued Operation, Operating Income (Loss)	16	59	53	94
Discontinued Operation, Tax Effect of Discontinued Operation	4	17	17	27
Discontinued Operation, Gain (Loss) from Disposal of Discontinued Operation, before Income Tax	1,087	(4)	1,036	(5)
Discontinued Operation, Tax Effect of Gain (Loss) from Disposal of Discontinued Operation	62	(1)	38	(1)
Earnings (loss) from discontinued operations	$ 1,037	$ 39	$ 1,034	$ 63

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

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