| Document And Entity Information | Jan. 29, 2025 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | Jan. 29, 2025 |
| Entity Registrant Name | SANFILIPPO JOHN B & SON INC |
| Entity Central Index Key | 0000880117 |
| Entity Emerging Growth Company | false |
| Entity File Number | 0-19681 |
| Entity Incorporation, State or Country Code | DE |
| Entity Tax Identification Number | 36-2419677 |
| Entity Address, Address Line One | 1703 N. RANDALL ROAD |
| Entity Address, City or Town | Elgin |
| Entity Address, State or Province | IL |
| Entity Address, Postal Zip Code | 60123-7820 |
| City Area Code | (847) |
| Local Phone Number | 289-1800 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of 12(b) Security | Common Stock, $.01 par value per share |
| Trading Symbol | JBSS |
| Security Exchange Name | NASDAQ |
