Discontinued Operations (Supplementary Cash Flow 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
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Discontinued Operations, Depreciation and Amortization			$ 44	$ 55
Discontinued Operations, Loss on sale of business			18	0
Discontinued Operations, Capital Expenditures			20	28
Sales of discontinued operations businesses, net of cash divested			54	0
Asset Impairment Accelerated Depreciation [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Discontinued Operations, Other Expense	$ 0	$ 619	$ 360	$ 694

Amount of capital expenditure attributable to discontinued operations.

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

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Amount of depreciation and amortization expense attributable to disposal group, including, but not limited to, discontinued operation.

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

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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This element represents the cash inflow during the period from the sale of a component of the entity.

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