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Discontinued Operations Discontinued Operations (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended					9 Months Ended
	Jul. 28, 2019	Apr. 28, 2019	Jan. 27, 2019	Oct. 28, 2018	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, Loss on sale of business						$ 18	$ 0
Discontinued Operation, Tax impact of loss on sale and costs associated with selling the business		$ 23			$ 0	21	0
Bolthouse Farms carrot and carrot ingredients reporting unit [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Tangible Asset Impairment Charges			$ 104			104
Bolthouse Farms carrot and carrot ingredients reporting unit [Member] \| Trademarks [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Impairment of Intangible Assets, Indefinite-lived (Excluding Goodwill)			18			18
Bolthouse Farms carrot and carrot ingredients reporting unit [Member] \| Customer Relationships [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Impairment of Intangible Assets, Finite-lived			40			40
Bolthouse Farms carrot and carrot ingredients reporting unit [Member] \| Developed Technology Rights [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Impairment of Intangible Assets, Finite-lived			15			15
Bolthouse Farms refrigerated beverages and salad dressing [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Tangible Asset Impairment Charges			9			9
Bolthouse Farms refrigerated beverages and salad dressing [Member] \| Trademarks [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Impairment of Intangible Assets, Indefinite-lived (Excluding Goodwill)			74			74
Bolthouse Farms refrigerated beverages and salad dressing [Member] \| Customer Relationships [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Impairment of Intangible Assets, Finite-lived			22			22
Garden Fresh Gourmet [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Tangible Asset Impairment Charges			2			2
Garden Fresh Gourmet [Member] \| Trademarks [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Impairment of Intangible Assets, Indefinite-lived (Excluding Goodwill)			23			23
Garden Fresh Gourmet [Member] \| Customer Relationships [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Impairment of Intangible Assets, Finite-lived			$ 39			39
U.S. Refrigerated Soup [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Tangible Asset Impairment Charges				$ 14		14
Campbell Fresh [Member] \| Costs Associated With Sale Of Business [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Discontinued Operations, Loss on sale of business		24			$ 0	31	$ 0
Bolthouse Farms [Member] \| Valuation Allowance, Deferred Tax Asset [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Discontinued Operation, Tax impact of loss on sale and costs associated with selling the business		29				29
U.S. Refrigerated Soup and Garden Fresh Gourmet
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from Divestiture of Businesses		55
U.S. Refrigerated Soup and Garden Fresh Gourmet \| Excluding Business Exit Costs [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Discontinued Operations, Loss on sale of business		$ 15				$ 18
Scenario, Forecast [Member] \| Bolthouse Farms [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from Divestiture of Businesses	$ 510