Disaggregation of Revenue - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 30, 2019	Mar. 31, 2018	Mar. 30, 2019	Mar. 31, 2018	Sep. 29, 2018
Disaggregation Of Revenue [Line Items]
Contract with customer, liability revenue recognized	$ 25,988	$ 22,738	$ 59,146	$ 53,821
Contract assets	$ 32,435		$ 32,435		$ 9,606
Propane [Member]
Disaggregation Of Revenue [Line Items]
Percentage of revenue generated from contract with customers	86.00%
Fuel Oil and Refined Fuels [Member]
Disaggregation Of Revenue [Line Items]
Percentage of revenue generated from contract with customers	8.00%
Natural Gas and Electricity [Member]
Disaggregation Of Revenue [Line Items]
Percentage of revenue generated from contract with customers	4.00%