Pension Plans and Other Postretirement Benefits - Components of Net Periodic Benefit Costs (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 30, 2023	Dec. 24, 2022
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Interest cost	$ 805	$ 827
Expected return on plan assets	(315)	(339)
Amortization of net (gain)	425	482
Net periodic benefit cost	915	970
Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Interest cost	36	41
Amortization of prior service credits	(65)	(124)
Amortization of net (gain)	(191)	(194)
Net periodic benefit cost	$ (220)	$ (277)