Segment Information - Disclosure by Reportable Segment and Reconciliation of Total Operating Segment Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 26, 2020	Sep. 28, 2019	Sep. 29, 2018
Revenues [Abstract]
Total revenues	$ 1,107,897	$ 1,267,705	$ 1,344,413
Operating income (loss):
Total operating income	140,270	150,854	158,003
Reconciliation to net income:
Loss on debt extinguishment	109	0	0
Interest expense, net	74,727	76,663	77,383
Other, net	4,822	4,702	4,692
(Benefit from) provision for income taxes	(146)	857	(606)
Net income	60,758	68,632	76,534
Depreciation and amortization [Abstract]
Total depreciation and amortization	116,791	120,872	125,222
Assets [Abstract]
Total assets	2,047,253	1,998,348
Operating/Reportable Segments [Member] | Propane [Member]
Revenues [Abstract]
Total revenues	955,143	1,083,446	1,153,323
Operating income (loss):
Total operating income	239,771	254,447	248,473
Depreciation and amortization [Abstract]
Total depreciation and amortization	106,725	108,763	111,460
Assets [Abstract]
Total assets	1,934,960	1,904,344
Operating/Reportable Segments [Member] | Fuel Oil and Refined Fuels [Member]
Revenues [Abstract]
Total revenues	75,039	92,084	91,520
Operating income (loss):
Total operating income	9,338	8,489	7,605
Depreciation and amortization [Abstract]
Total depreciation and amortization	1,843	2,083	2,574
Assets [Abstract]
Total assets	47,063	44,279
Operating/Reportable Segments [Member] | Natural Gas and Electricity [Member]
Revenues [Abstract]
Total revenues	31,184	45,206	54,308
Operating income (loss):
Total operating income	7,459	8,758	12,309
Depreciation and amortization [Abstract]
Total depreciation and amortization	18	0	0
Assets [Abstract]
Total assets	10,594	11,907
Operating/Reportable Segments [Member] | All Other [Member]
Revenues [Abstract]
Total revenues	46,531	46,969	45,262
Operating income (loss):
Total operating income	(20,377)	(19,516)	(20,145)
Depreciation and amortization [Abstract]
Total depreciation and amortization	189	196	215
Assets [Abstract]
Total assets	18,733	2,950
Operating/Reportable Segments [Member] | Corporate [Member]
Operating income (loss):
Total operating income	(95,921)	(101,324)	(90,239)
Depreciation and amortization [Abstract]
Total depreciation and amortization	8,016	9,830	$ 10,973
Assets [Abstract]
Total assets	$ 35,903	$ 34,868