Financial Instruments and Risk Management - Fair Value of the Partnership's Senior Notes (Details) - USD ($) $ in Thousands	Mar. 28, 2026	Sep. 27, 2025
Bank Debt and Senior Notes [Abstract]
Fair value of Senior Notes	$ 1,021,364	$ 1,037,715
5.875% Senior Notes due March 1, 2027 [Member]
Bank Debt and Senior Notes [Abstract]
Fair value of Senior Notes	0	349,125
5.00% Senior Notes due June 1, 2031 [Member]
Bank Debt and Senior Notes [Abstract]
Fair value of Senior Notes	612,625	617,500
6.50% Senior Notes due December 15, 2035 [Member]
Bank Debt and Senior Notes [Abstract]
Fair value of Senior Notes	340,375	0
5.50% Green Bonds Due October 1, 2028 through October 1, 2033 [Member]
Bank Debt and Senior Notes [Abstract]
Fair value of Senior Notes	$ 68,364	$ 71,090

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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+ Details

SUBURBAN PROPANE PARTNERS LP 10-Q