Condensed Financial Information of Registrant (Details 2) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2012
Cash flows provided by (used in) operating activities:
Net cash provided by (used in) operating activities (a)	$ 105,828	$ 39,402	$ 44,429
Cash flows provided by (used in) investing activities:
Net cash provided by (used in) investing activities	(44,517)	(15,928)	(73,956)
Cash flows provided by (used in) financing activities:
Repayment of debt		(82,499)	(50,854)
Proceeds from the issuance of debt		124,188
Debt extinguishment costs		(1,409)
Distributions	(19,525)	(20,677)	(20,353)
Unit repurchase	(19,648)	(10,949)	(33,234)
Net cash provided by (used in) financing activities	(40,009)	2,253	(104,571)
Net increase in cash	21,302	25,727	(134,098)
Cash and equivalent at beginning of period	86,789	61,062	195,160	108,091
STAR GAS PARTNERS, L.P. [Member]
Cash flows provided by (used in) operating activities:
Net cash provided by (used in) operating activities (a)	39,196	(4,813)	104,625
Cash flows provided by (used in) investing activities:
Net cash provided by (used in) investing activities
Cash flows provided by (used in) financing activities:
Repayment of debt		(82,499)	(50,854)
Proceeds from the issuance of debt		124,188
Debt extinguishment costs		(1,409)
Distributions	(19,525)	(20,677)	(20,353)
Unit repurchase	(19,648)	(10,949)	(33,234)
Increase in deferred charges		(3,777)
Net cash provided by (used in) financing activities	(39,173)	4,877	(104,441)
Net increase in cash	23	64	184
Cash and equivalent at beginning of period	$ 294	$ 230	$ 46	$ 317