Segment Information - Disclosure by Reportable Segment and Reconciliation of Total Operating Segment Information (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Jun. 30, 2018	Jun. 24, 2017	Jun. 30, 2018	Jun. 24, 2017	Sep. 30, 2017
Revenues [Abstract]
Total revenues		$ 241,936	$ 222,895	$ 1,151,495	$ 990,780
Operating income (loss):
Total operating income (loss)		3,061	(11,062)	185,039	145,280
Reconciliation to net (loss) income:
Loss on debt extinguishment		0	0	0	1,567
Interest expense, net		19,512	18,502	58,428	54,820
Provision for (benefit from) income taxes		144	152	(749)	308
Net (loss) income		(16,595)	(29,716)	127,360	88,585
Depreciation and amortization [Abstract]
Total depreciation and amortization		31,259	31,825	94,593	95,756
Assets [Abstract]
Total assets		2,131,533		2,131,533		$ 2,171,283
Operating/Reportable Segments [Member] | Propane [Member]
Revenues [Abstract]
Total revenues		205,400	188,406	990,344	843,519
Operating income (loss):
Total operating income (loss)	[1]	28,073	11,323	245,845	201,332
Depreciation and amortization [Abstract]
Total depreciation and amortization		27,875	27,787	83,944	83,243
Assets [Abstract]
Total assets		2,020,928		2,020,928		2,066,997
Operating/Reportable Segments [Member] | Fuel Oil and Refined Fuels [Member]
Revenues [Abstract]
Total revenues		15,400	12,886	82,414	69,612
Operating income (loss):
Total operating income (loss)		(891)	199	10,132	9,875
Depreciation and amortization [Abstract]
Total depreciation and amortization		571	625	1,866	1,923
Assets [Abstract]
Total assets		49,525		49,525		49,863
Operating/Reportable Segments [Member] | Natural Gas and Electricity [Member]
Revenues [Abstract]
Total revenues		10,403	11,923	43,942	44,229
Operating income (loss):
Total operating income (loss)		2,192	2,806	11,131	11,461
Depreciation and amortization [Abstract]
Total depreciation and amortization		0	0	0	0
Assets [Abstract]
Total assets		12,679		12,679		12,455
Operating/Reportable Segments [Member] | All Other [Member]
Revenues [Abstract]
Total revenues		10,733	9,680	34,795	33,420
Operating income (loss):
Total operating income (loss)		(4,607)	(5,747)	(14,821)	(16,139)
Depreciation and amortization [Abstract]
Total depreciation and amortization		57	76	163	222
Assets [Abstract]
Total assets		3,576		3,576		2,147
Operating/Reportable Segments [Member] | Corporate [Member]
Operating income (loss):
Total operating income (loss)		(21,706)	(19,643)	(67,248)	(61,249)
Depreciation and amortization [Abstract]
Total depreciation and amortization		2,756	$ 3,337	8,620	$ 10,368
Assets [Abstract]
Total assets		$ 44,825		$ 44,825		$ 39,821

[1] Includes the loss on sale of business of $4,823 for the nine months ended June 30, 2018 (see Note 3).