| Cover | Dec. 23, 2019 | Dec. 22, 2019 |
| Cover [Abstract] | ||
| Document Type | 8-K | |
| Amendment Flag | false | |
| Document Period End Date | Dec. 23, 2019 | |
| Entity File Number | 1-3822 | |
| Entity Registrant Name | CAMPBELL SOUP COMPANY | |
| Entity Central Index Key | 0000016732 | |
| Entity Tax Identification Number | 21-0419870 | |
| Entity Incorporation, State or Country Code | NJ | |
| Entity Address, Address Line One | One Campbell Place | |
| Entity Address, City or Town | Camden | |
| Entity Address, State or Province | NJ | |
| Entity Address, Postal Zip Code | 08103-1799 | |
| City Area Code | 856 | |
| Local Phone Number | 342-4800 | |
| Written Communications | false | |
| Soliciting Material | false | |
| Pre-commencement Tender Offer | false | |
| Pre-commencement Issuer Tender Offer | false | |
| Title of 12(b) Security | Capital Stock, par value $.0375 | |
| Trading Symbol | CPB | |
| Security Exchange Name | NYSE | |
| Entity Emerging Growth Company | false |
