Defined Benefit Pension Plans - Fair Value Hierarchy of Benefit Plan Assets (Details) - USD ($) $ in Thousands	Sep. 25, 2022	Sep. 26, 2021	Sep. 27, 2020
NAV | Hedge fund investments
Defined Benefit Plan Disclosure [Line Items]
Pension assets	$ 32,515	$ 3,235
Level 1 | Hedge fund investments
Defined Benefit Plan Disclosure [Line Items]
Pension assets	0	0
Level 2 | Hedge fund investments
Defined Benefit Plan Disclosure [Line Items]
Pension assets	0	0
Level 3 | Hedge fund investments
Defined Benefit Plan Disclosure [Line Items]
Pension assets	0	0
Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Pension assets	209,356	398,430	$ 331,354
Pension Plan | NAV | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Pension assets	0	0
Pension Plan | NAV | Domestic equity securities
Defined Benefit Plan Disclosure [Line Items]
Pension assets	2,235	7,236
Pension Plan | NAV | International equity securities
Defined Benefit Plan Disclosure [Line Items]
Pension assets	0	0
Pension Plan | NAV | Emerging equity securities
Defined Benefit Plan Disclosure [Line Items]
Pension assets	0	0
Pension Plan | NAV | TIPS
Defined Benefit Plan Disclosure [Line Items]
Pension assets		0
Pension Plan | NAV | Debt Securities
Defined Benefit Plan Disclosure [Line Items]
Pension assets	0	0
Pension Plan | NAV | Hedge fund investments
Defined Benefit Plan Disclosure [Line Items]
Pension assets		18,758
Pension Plan | Level 1 | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Pension assets	1,562	4,447
Pension Plan | Level 1 | Domestic equity securities
Defined Benefit Plan Disclosure [Line Items]
Pension assets	67,661	78,577
Pension Plan | Level 1 | International equity securities
Defined Benefit Plan Disclosure [Line Items]
Pension assets	5,743	9,485
Pension Plan | Level 1 | Emerging equity securities
Defined Benefit Plan Disclosure [Line Items]
Pension assets	4,996	8,077
Pension Plan | Level 1 | TIPS
Defined Benefit Plan Disclosure [Line Items]
Pension assets		7,280
Pension Plan | Level 1 | Debt Securities
Defined Benefit Plan Disclosure [Line Items]
Pension assets	25,742	181,908
Pension Plan | Level 1 | Hedge fund investments
Defined Benefit Plan Disclosure [Line Items]
Pension assets		0
Pension Plan | Level 2 | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Pension assets	0	0
Pension Plan | Level 2 | Domestic equity securities
Defined Benefit Plan Disclosure [Line Items]
Pension assets	0	42,448
Pension Plan | Level 2 | International equity securities
Defined Benefit Plan Disclosure [Line Items]
Pension assets	4,519	9,505
Pension Plan | Level 2 | Emerging equity securities
Defined Benefit Plan Disclosure [Line Items]
Pension assets	0	0
Pension Plan | Level 2 | TIPS
Defined Benefit Plan Disclosure [Line Items]
Pension assets		0
Pension Plan | Level 2 | Debt Securities
Defined Benefit Plan Disclosure [Line Items]
Pension assets	65,364	32,781
Pension Plan | Level 2 | Hedge fund investments
Defined Benefit Plan Disclosure [Line Items]
Pension assets		0
Pension Plan | Level 3 | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Pension assets	0	0
Pension Plan | Level 3 | Domestic equity securities
Defined Benefit Plan Disclosure [Line Items]
Pension assets	0	0
Pension Plan | Level 3 | International equity securities
Defined Benefit Plan Disclosure [Line Items]
Pension assets	0	0
Pension Plan | Level 3 | Emerging equity securities
Defined Benefit Plan Disclosure [Line Items]
Pension assets	0	0
Pension Plan | Level 3 | TIPS
Defined Benefit Plan Disclosure [Line Items]
Pension assets		0
Pension Plan | Level 3 | Debt Securities
Defined Benefit Plan Disclosure [Line Items]
Pension assets	$ 0	0
Pension Plan | Level 3 | Hedge fund investments
Defined Benefit Plan Disclosure [Line Items]
Pension assets		$ 0