Document and Entity Information - USD ($)	12 Months Ended
	Sep. 30, 2015	Nov. 30, 2015	Mar. 31, 2015
Document Information [Line Items]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Sep. 30, 2015
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	FY
Trading Symbol	SGU
Entity Registrant Name	STAR GAS PARTNERS LP
Entity Central Index Key	0001002590
Current Fiscal Year End Date	--09-30
Entity Well-known Seasoned Issuer	No
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		57,282,352
Entity Public Float			$ 321,232,000