Segment Information - Disclosure by Reportable Segment and Reconciliation of Total Operating Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 26, 2016	Mar. 28, 2015	Mar. 26, 2016	Mar. 28, 2015	Sep. 26, 2015
Revenues [Abstract]
Total revenues	$ 404,140	$ 599,389	$ 679,997	$ 1,022,333
Operating income (loss) [Abstract]:
Total operating income	111,213	171,591	142,557	247,559
Reconciliation to net income:
Loss on debt extinguishment	292	15,072	292	15,072
Interest expense, net	18,852	19,711	37,745	39,710
Provision for income taxes	58	174	243	336
Net income	92,011	136,634	104,277	192,441
Depreciation and amortization [Abstract]
Total depreciation and amortization	33,150	33,229	64,788	65,858
Assets [Abstract]
Total assets	2,439,691		2,439,691		$ 2,485,730
Operating/Reportable Segments [Member] | Propane [Member]
Revenues [Abstract]
Total revenues	348,216	498,616	579,691	853,266
Operating income (loss) [Abstract]:
Total operating income	129,277	189,265	184,860	292,341
Depreciation and amortization [Abstract]
Total depreciation and amortization	27,518	27,562	54,625	54,641
Assets [Abstract]
Total assets	2,246,909		2,246,909		2,209,343
Operating/Reportable Segments [Member] | Fuel Oil and Refined Fuels [Member]
Revenues [Abstract]
Total revenues	28,814	60,426	49,502	99,356
Operating income (loss) [Abstract]:
Total operating income	6,470	9,434	8,439	10,880
Depreciation and amortization [Abstract]
Total depreciation and amortization	686	728	1,382	1,561
Assets [Abstract]
Total assets	58,166		58,166		58,077
Operating/Reportable Segments [Member] | Natural Gas and Electricity [Member]
Revenues [Abstract]
Total revenues	15,962	28,281	27,636	44,248
Operating income (loss) [Abstract]:
Total operating income	4,444	7,457	6,696	10,215
Depreciation and amortization [Abstract]
Total depreciation and amortization	1	2	3	4
Assets [Abstract]
Total assets	15,068		15,068		13,253
Operating/Reportable Segments [Member] | All Other [Member]
Revenues [Abstract]
Total revenues	11,148	12,066	23,168	25,463
Operating income (loss) [Abstract]:
Total operating income	(5,812)	(5,289)	(12,868)	(10,967)
Depreciation and amortization [Abstract]
Total depreciation and amortization	79	69	161	149
Assets [Abstract]
Total assets	2,510		2,510		2,888
Operating/Reportable Segments [Member] | Corporate [Member]
Operating income (loss) [Abstract]:
Total operating income	(23,166)	(29,276)	(44,570)	(54,910)
Depreciation and amortization [Abstract]
Total depreciation and amortization	4,866	$ 4,868	8,617	$ 9,503
Assets [Abstract]
Total assets	$ 117,038		$ 117,038		$ 202,169