| Document and Entity Information | May 10, 2021 |
| Cover [Abstract] | |
| Entity Registrant Name | SUBURBAN PROPANE PARTNERS LP |
| Entity Address, State or Province | NJ |
| Amendment Flag | false |
| Entity Central Index Key | 0001005210 |
| Document Type | 8-K |
| Document Period End Date | May 10, 2021 |
| Entity File Number | 1-14222 |
| Entity Incorporation State Country Code | DE |
| Entity Tax Identification Number | 22-3410353 |
| Entity Address, Address Line One | 240 Route 10 West |
| Entity Address, City or Town | Whippany |
| Entity Address, Postal Zip Code | 07981 |
| City Area Code | (973) |
| Local Phone Number | 887-5300 |
| Written Communications | false |
| Soliciting Material | false |
| Pre Commencement Tender Offer | false |
| Pre Commencement Issuer Tender Offer | false |
| Security 12b Title | Common Units |
| Trading Symbol | SPH |
| Security Exchange Name | NYSE |
| Entity Emerging Growth Company | false |
