Segment Information - Disclosure by Reportable Segment and Reconciliation of Total Operating Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Sep. 28, 2019
Revenues [Abstract]
Total revenues	$ 333,878	$ 377,104
Operating income:
Total operating income	59,854	48,534
Reconciliation to net income:
Interest expense, net	19,072	19,488
Other, net	978	1,176
(Benefit from) provision for income taxes	(359)	151
Net income	40,163	27,719
Depreciation and amortization [Abstract]
Total depreciation and amortization	29,274	30,071
Assets [Abstract]
Total assets	2,184,409		$ 1,998,348
Operating/Reportable Segments [Member] | Propane [Member]
Revenues [Abstract]
Total revenues	285,425	321,360
Operating income:
Total operating income	86,122	70,471
Depreciation and amortization [Abstract]
Total depreciation and amortization	26,980	26,955
Assets [Abstract]
Total assets	2,054,338		1,904,344
Operating/Reportable Segments [Member] | Fuel Oil and Refined Fuels [Member]
Revenues [Abstract]
Total revenues	25,891	28,909
Operating income:
Total operating income	2,728	3,470
Depreciation and amortization [Abstract]
Total depreciation and amortization	507	522
Assets [Abstract]
Total assets	57,367		44,279
Operating/Reportable Segments [Member] | Natural Gas and Electricity [Member]
Revenues [Abstract]
Total revenues	8,721	13,404
Operating income:
Total operating income	2,229	2,828
Depreciation and amortization [Abstract]
Total depreciation and amortization	0	0
Assets [Abstract]
Total assets	13,602		11,907
Operating/Reportable Segments [Member] | All Other [Member]
Revenues [Abstract]
Total revenues	13,841	13,431
Operating income:
Total operating income	(5,387)	(4,644)
Depreciation and amortization [Abstract]
Total depreciation and amortization	47	52
Assets [Abstract]
Total assets	13,021		2,950
Operating/Reportable Segments [Member] | Corporate [Member]
Operating income:
Total operating income	(25,838)	(23,591)
Depreciation and amortization [Abstract]
Total depreciation and amortization	1,740	$ 2,542
Assets [Abstract]
Total assets	$ 46,081		$ 34,868