Document and Entity Information - shares	9 Months Ended
	Jun. 30, 2017	Jul. 31, 2017
Document Information [Line Items]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 30, 2017
Document Fiscal Year Focus	2017
Document Fiscal Period Focus	Q3
Trading Symbol	SGU
Entity Registrant Name	STAR GAS PARTNERS LP
Entity Central Index Key	0001002590
Current Fiscal Year End Date	--09-30
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		55,887,832