Selected Balance Sheet and Statement of Operations Information - Other, Net (Details) - USD ($) $ in Thousands		12 Months Ended
		Sep. 27, 2025	Sep. 28, 2024	Sep. 30, 2023
Property, Plant and Equipment [Line Items]
Equity in losses		$ (29,891)	$ (18,119)	$ (6,264)
Contingent consideration from Equilibrium		(3,000)	0	0
Reversal of the earnout reserve established in connection with the RNG acquisition	[1]	(6,194)	0	0
Other		(4,474)	(4,058)	(1,517)
Other, net		22,128	21,537	9,036
Other Noncash Income Expense [Member]
Property, Plant and Equipment [Line Items]
Other	[2]	1,431	3,418	2,772
Oberon
Property, Plant and Equipment [Line Items]
Equity in losses	[3]	12,358	16,042	4,698
IH
Property, Plant and Equipment [Line Items]
Equity in losses	[4]	11,438	2,077	1,566
Impairment of Cost Method Investee [Member]
Property, Plant and Equipment [Line Items]
Equity in losses	[5]	$ 6,095	$ 0	$ 0

[1] Represents an adjustment to the fair value of the Partnership's contingent consideration liability (see Note 4 above).

[2] net periodic benefits costs for the Partnership's pension and other postretirement benefit plans and pension settlement charges (see Note 12 below).

[3] Fiscal 2025 included an other-than-temporary impairment charge of $10,213 (see Note 4 above).

[4] Fiscal 2025 included an other-than-temporary impairment charge of $9,595 (see Note 4 above).

[5] Fiscal 2025 included an other-than-temporary impairment charge of $6,095 (see Note 4 above).