Document and Entity Information - USD ($)	12 Months Ended
	Sep. 25, 2021	Nov. 22, 2021	Mar. 26, 2021
Cover [Abstract]
Entity Registrant Name	SUBURBAN PROPANE PARTNERS LP
Entity Central Index Key	0001005210
Current Fiscal Year End Date	--09-25
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Public Float			$ 941,690,000
Entity Common Stock, Shares Outstanding		62,963,712
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	FY
Entity File Number	1-14222
Document Type	10-K
Trading Symbol	SPH
Security Exchange Name	NYSE
Title of 12(g) Security	Common Units
Amendment Flag	false
Document Period End Date	Sep. 25, 2021
Entity Interactive Data Current	Yes
Entity Incorporation, State or 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, State or Province	NJ
Entity Address, Postal Zip Code	07981
City Area Code	973
Local Phone Number	887-5300
Document Annual Report	true
Document Transition Report	false
Documents Incorporated by Reference	None
ICFR Auditor Attestation Flag	true