Divestitures (Schedule of Assets and Liabilites of Discontinued Operations) (Details) - USD ($) $ in Millions	Apr. 26, 2020	Jul. 28, 2019	Apr. 28, 2019	Jul. 29, 2018
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Cash and Cash Equivalents	$ 0	$ 148	$ 161	$ 177
Disposal Group, Including Discontinued Operation, Assets, Current, Total	0	428
Current liabilities of discontinued operations	$ 0	469
Campbell International [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Cash and Cash Equivalents		148
Disposal Group, Including Discontinued Operation, Accounts, Notes and Loans Receivable, Net		135
Disposal Group, Including Discontinued Operation, Inventory		135
Disposal Group, Including Discontinued Operation, Other Assets, Current		10
Disposal Group, Including Discontinued Operation, Assets, Current, Total		428
Disposal Group, Including Discontinued Operation, Property, Plant and Equipment, Noncurrent		340
Disposal Group, Including Discontinued Operation, Goodwill		661
Disposal Group, Including Discontinued Operation, Intangible Assets		135
Disposal Group, Including Discontinued Operation, Other Assets, Noncurrent		31
Disposal Group, Including Discontinued Operation, Assets, Total		1,595
Disposal Group, Including Discontinued Operation, Accounts Payable		109
Disposal Group, Including Discontinued Operation, Accrued Liabilities		114
Disposal Group, Including Discontinued Operation, Accrued Income Tax Payable		14
Current liabilities of discontinued operations		469
Disposal Group, Including Discontinued Operation, Other Liabilities, Noncurrent		27
Disposal Group, Including Discontinued Operation, Deferred Tax Liabilities		32
Disposal Group, Including Discontinued Operation, Liabilities		534
Debt [Member] | Campbell International [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Other Liabilities, Current		232
Disposal Group, Including Discontinued Operation, Other Liabilities, Noncurrent		$ 6