Unit-Based Compensation Arrangements - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2023	Sep. 24, 2022	Sep. 25, 2021
Distribution Equivalent Rights Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Compensation expense	$ 1,344	$ 1,189	$ 874
Distribution Equivalent Rights Plan, terms	On January 17, 2017, the Partnership adopted the Distribution Equivalent Rights Plan (the “DER Plan”), as amended on November 8, 2022, which gives the Compensation Committee discretion to award distribution equivalent rights (“DERs”) to executive officers of the Partnership. Once awarded, DERs entitle the grantee to a cash payment each time the Board of Supervisors declares a cash distribution on the Partnership’s Common Units, which cash payment will be equal to an amount calculated by multiplying the number of unvested restricted units and unvested phantom units which are held by the grantee on the record date of the distribution, by the amount of the declared distribution per Common Unit.
Phantom Equity Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Compensation expense	$ 3,668
Liability included within accrued employment and benefit costs (or other liabilities, as applicable) related to estimated future payments under the LTIP	3,668
Restricted Stock Units (RSUs) [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized compensation cost	$ 2,984
Weighted-average recognition period of compensation cost	1 year 2 months 12 days
Compensation expense	$ 8,260	$ 11,253	$ 10,073
Restricted Stock Units (RSUs) [Member] | Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total number of Common Units authorized for issuance (in units)	1,800,000
2018 Restricted Unit Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Additional number of Common Units authorized for issuance (in units)	172,500
Awards Granted	571,732	884,658	779,837
Restricted Unit Plans, terms of award	Unless otherwise determined by the Compensation Committee of the Partnership’s Board of Supervisors (the “Compensation Committee”) on or before the grant date, one-third of all outstanding awards under the Restricted Unit Plan will vest on each of the first three anniversaries of the award grant date. Participants in the Restricted Unit Plan are not eligible to receive quarterly distributions on, or vote, their respective restricted units until vested. Restricted units cannot be sold or transferred prior to vesting. The value of each restricted unit is established by the market price of the Common Unit on the date of grant, net of estimated future distributions during the vesting period. Restricted units are subject to forfeiture in certain circumstances as defined in the Restricted Unit Plan. Compensation expense for the unvested awards is recognized ratably over the vesting periods and is net of estimated forfeitures.
2018 Restricted Unit Plan [Member] | Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total number of Common Units authorized for issuance (in units)	3,525,000
Long-Term Incentive Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Long-Term Incentive Plan, terms of award	The LTIPs are non-qualified, unfunded, long-term incentive plans for executive officers and key employees that provide for payment, in the form of cash, of an award of equity-based compensation at the end of a three-year performance period.
Measurement period of average distribution coverage ratio	3 years
Long-Term Incentive Plan, compensation earned, description	The level of compensation earned under the fiscal 2021 award is evaluated using two separate measurement components: (i) 75% weight based on the level of average distributable cash flow of the Partnership over the three-year measurement period; and (ii) 25% weight based on the achievement of certain operating and strategic objectives, set by the Compensation Committee, over that award’s three-year measurement period. The level of compensation earned under the fiscal 2022 award, and measurement periods thereafter, is also evaluated using two separate measurement components: (i) 50% weight based on the level of average distributable cash flow of the Partnership over the three-year measurement period; and (ii) 50% weight based on the achievement of certain operating and strategic objectives, set by the Compensation Committee for that award’s three-year measurement period.
Compensation expense (income)	$ 3,771	$ 6,112	$ 4,819
Cash payouts	$ 3,129	$ 3,985	$ 3,354