Financial Instruments and Risk Management - Fair Value of the Partnership's Derivative Instruments and their Location in the Condensed Consolidated Balance Sheets (Details) - USD ($) $ in Thousands	Dec. 29, 2018	Sep. 29, 2018
Commodity-Related Derivatives [Member]
Derivatives Fair Value [Line Items]
Fair value - assets	$ 7,386	$ 23,181
Fair value - liabilities	13,504	14,582
Derivatives Not Designated as Hedging Instruments [Member]
Derivatives Fair Value [Line Items]
Fair value - assets	5,999	14,888
Fair value - liabilities	12,117	6,289
Derivatives Not Designated as Hedging Instruments [Member] | Commodity-Related Derivatives [Member] | Other Current Assets [Member]
Derivatives Fair Value [Line Items]
Fair value - assets	5,924	14,875
Derivatives Not Designated as Hedging Instruments [Member] | Commodity-Related Derivatives [Member] | Other Assets [Member]
Derivatives Fair Value [Line Items]
Fair value - assets	75	13
Derivatives Not Designated as Hedging Instruments [Member] | Commodity-Related Derivatives [Member] | Other Current Liabilities [Member]
Derivatives Fair Value [Line Items]
Fair value - liabilities	12,117	6,122
Derivatives Not Designated as Hedging Instruments [Member] | Commodity-Related Derivatives [Member] | Other Liabilities [Member]
Derivatives Fair Value [Line Items]
Fair value - liabilities	$ 0	$ 167