Recent Accounting Pronouncements Schedule of Changes (Details) - USD ($) $ / shares in Units, $ in Millions		3 Months Ended			9 Months Ended
		Apr. 28, 2019		Apr. 29, 2018	Apr. 28, 2019		Apr. 29, 2018	Jan. 27, 2019	Jul. 29, 2018	Jan. 28, 2018	Jul. 30, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Accounts receivable, net		$ 753			$ 753				$ 702
Assets, Current		2,161			2,161				2,296
Assets		13,768			13,768				14,529
Payable to suppliers and others		841			841				814
Accrued liabilities		672			672				637
Accrued income taxes		18			18				22
Total current liabilities		3,511			3,511				3,594
Total liabilities		12,531			12,531				13,156
Earnings retained in the business		2,107			2,107				2,224
Total Campbell Soup Company shareholders' equity		1,228			1,228				1,364
Total equity		1,237		$ 1,411	1,237		$ 1,411	$ 1,278	1,373	$ 1,949	$ 1,645
Liabilities and Equity		13,768			13,768				$ 14,529
Net sales		2,178		1,878	7,129		5,743
Cost of products sold		1,455		1,263	4,781		3,624
Costs and Expenses		1,912		1,720	6,119		4,843
Earnings before interest and taxes		266		158	1,010		900
Earnings (loss) before taxes		175		116	734		796
Taxes on earnings		44		43	184		106
Earnings from continuing operations attributable to Campbell Soup Company		$ 131		$ 73	$ 550		$ 690
Earnings from continuing operations attributable to Campbell Soup Company		$ 0.44	[1]	$ 0.24	$ 1.83	[1]	$ 2.29
Earnings from continuing operations attributable to Campbell Soup Company		$ 0.43		$ 0.24	$ 1.82		$ 2.28
Balances without adoption of Topic 606
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Accounts receivable, net		$ 752			$ 752
Assets, Current		2,160			2,160
Assets		13,767			13,767
Payable to suppliers and others		840			840
Accrued liabilities		661			661
Accrued income taxes		21			21
Total current liabilities		3,502			3,502
Total liabilities		12,522			12,522
Earnings retained in the business		2,115			2,115
Total Campbell Soup Company shareholders' equity		1,236			1,236
Total equity		1,245			1,245
Liabilities and Equity		13,767			13,767
Net sales		2,172			7,128
Cost of products sold		1,454			4,780
Costs and Expenses		1,911			6,118
Earnings before interest and taxes		261			1,010
Earnings (loss) before taxes		170			734
Taxes on earnings		43			184
Earnings from continuing operations attributable to Campbell Soup Company		$ 127			$ 550
Earnings from continuing operations attributable to Campbell Soup Company	[1]	$ 0.42			$ 1.83
Earnings from continuing operations attributable to Campbell Soup Company		$ 0.42			$ 1.82
Adjustments due to adoption of Topic 606
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Accounts receivable, net		$ 1			$ 1
Assets, Current		1			1
Assets		1			1
Payable to suppliers and others		1			1
Accrued liabilities		11			11
Accrued income taxes		(3)			(3)
Total current liabilities		9			9
Total liabilities		9			9
Earnings retained in the business		(8)			(8)
Total Campbell Soup Company shareholders' equity		(8)			(8)
Total equity		(8)			(8)
Liabilities and Equity		1			1
Net sales		6			1
Cost of products sold		1			1
Costs and Expenses		1			1
Earnings before interest and taxes		5			0
Earnings (loss) before taxes		5			0
Taxes on earnings		1			0
Earnings from continuing operations attributable to Campbell Soup Company		$ 4			$ 0
Earnings from continuing operations attributable to Campbell Soup Company	[1]	$ 0.01			$ 0.00
Earnings from continuing operations attributable to Campbell Soup Company		$ 0.01			$ 0.00

[1] The sum of individual per share amounts may not add due to rounding.