Recent Accounting Pronouncements Schedule of Changes (Details) - USD ($) $ / shares in Units, $ in Millions		3 Months Ended			6 Months Ended
		Jan. 27, 2019		Jan. 28, 2018	Jan. 27, 2019		Jan. 28, 2018	Oct. 28, 2018	Jul. 29, 2018	Oct. 29, 2017	Jul. 30, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Accounts receivable, net		$ 927			$ 927				$ 785
Assets, Current		2,295			2,295				2,296
Assets		14,024			14,024				14,529
Payable to suppliers and others		930			930				893
Accrued liabilities		784			784				676
Accrued income taxes		24			24				22
Total current liabilities		3,299			3,299				3,594
Total liabilities		12,746			12,746				13,156
Earnings retained in the business		2,130			2,130				2,224
Total Campbell Soup Company shareholders' equity		1,269			1,269				1,364
Total equity		1,278		$ 1,949	1,278		$ 1,949	$ 1,415	1,373	$ 1,689	$ 1,645
Liabilities and Equity		14,024			14,024				$ 14,529
Net sales		2,713		2,180	5,407		4,341
Earnings before interest and taxes		19		243	369		655
Earnings (loss) before taxes		(73)		211	184		593
Taxes on earnings		(14)		(74)	49		33
Net earnings (loss) attributable to Campbell Soup Company		$ (59)		$ 285	$ 135		$ 560
Per Share - Basic
Net earnings (loss) attributable to Campbell Soup Company		$ (0.20)	[1]	$ 0.95	$ 0.45	[1]	$ 1.86
Per Share - Assuming Dilution
Net earnings attributable to Campbell Soup Company		$ (0.20)	[1]	$ 0.95	$ 0.45	[1]	$ 1.85
Balances without adoption of Topic 606
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Accounts receivable, net		$ 926			$ 926
Assets, Current		2,294			2,294
Assets		14,023			14,023
Payable to suppliers and others		929			929
Accrued liabilities		768			768
Accrued income taxes		28			28
Total current liabilities		3,286			3,286
Total liabilities		12,733			12,733
Earnings retained in the business		2,142			2,142
Total Campbell Soup Company shareholders' equity		1,281			1,281
Total equity		1,290			1,290
Liabilities and Equity		14,023			14,023
Net sales		2,702			5,412
Earnings before interest and taxes		8			374
Earnings (loss) before taxes		(84)			189
Taxes on earnings		(17)			50
Net earnings (loss) attributable to Campbell Soup Company		$ (67)			$ 139
Per Share - Basic
Net earnings (loss) attributable to Campbell Soup Company	[1]	$ (0.22)			$ 0.46
Per Share - Assuming Dilution
Net earnings attributable to Campbell Soup Company	[1]	$ (0.22)			$ 0.46
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		16			16
Accrued income taxes		(4)			(4)
Total current liabilities		13			13
Total liabilities		13			13
Earnings retained in the business		(12)			(12)
Total Campbell Soup Company shareholders' equity		(12)			(12)
Total equity		(12)			(12)
Liabilities and Equity		1			1
Net sales		11			(5)
Earnings before interest and taxes		11			(5)
Earnings (loss) before taxes		11			(5)
Taxes on earnings		3			(1)
Net earnings (loss) attributable to Campbell Soup Company		$ 8			$ (4)
Per Share - Basic
Net earnings (loss) attributable to Campbell Soup Company	[1]	$ 0.03			$ (0.01)
Per Share - Assuming Dilution
Net earnings attributable to Campbell Soup Company	[1]	$ 0.03			$ (0.01)

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