Discontinued Operations (Schedule of Results of Operations of Discontinued Operations) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Apr. 28, 2019	Apr. 29, 2018	Apr. 28, 2019	Apr. 29, 2018
Discontinued Operations, Net sales	$ 210	$ 247	$ 666	$ 723
Discontinued Operations, Earnings (loss) before taxes from operations	7	(633)	(361)	(720)
Discontinued Operation, Taxes on earnings from operations	7	(167)	(82)	(197)
Discontinued Operations, Loss on sale of business / costs associated with selling the business			18	0
Discontinued Operation, Tax impact of loss on sale and costs associated with selling the business	23	0	21	0
Loss from discontinued operations	(47)	(466)	(331)	(523)
Asset Impairment Accelerated Depreciation [Member]
Discontinued Operations, Other Expense	0	(619)	(360)	(694)
Campbell Fresh [Member] \| Costs Associated With Sale Of Business [Member]
Discontinued Operations, Loss on sale of business / costs associated with selling the business	$ 24	$ 0	$ 31	$ 0

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

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Amount of tax expense (benefit) related to a discontinued operation. Includes, but is not limited to, tax expense (benefit) related to income (loss) from operations during the phase-out period, tax expense (benefit) related to gain (loss) on disposal, tax expense (benefit) related to gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and tax expense (benefit) related to adjustments of a prior period gain (loss) on disposal.

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

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Amount of revenue attributable to disposal group, including, but not limited to, discontinued operation.

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Amount after tax of income (loss) from a discontinued operation including the portion attributable to the noncontrolling interest. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal.

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