Restructuring and Asset Impairments - Schedule of Restructuring and Restructuring-Related Asset Impairment Expenses by Type Incurred and by Reportable Segment (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 28, 2026	Jun. 29, 2025	Jun. 28, 2026	Jun. 29, 2025
Restructuring Cost and Reserve [Line Items]
Restructuring and restructuring-related asset impairment charges, net	$ 1,933	$ 9,752	$ 17,066	$ 23,333
Other asset impairments	0	0	0	0
Restructuring/Asset impairment charges, net	1,933	9,752	17,066	23,333
Operating Segments \| Consumer Packaging
Restructuring Cost and Reserve [Line Items]
Restructuring and restructuring-related asset impairment charges, net	(170)	1,509	8,937	2,738
Operating Segments \| Industrial Paper Packaging
Restructuring Cost and Reserve [Line Items]
Restructuring and restructuring-related asset impairment charges, net	1,237	8,234	7,196	20,732
All Other
Restructuring Cost and Reserve [Line Items]
Restructuring and restructuring-related asset impairment charges, net	0	16	0	21
Corporate
Restructuring Cost and Reserve [Line Items]
Restructuring and restructuring-related asset impairment charges, net	866	(7)	933	(158)
Severance and Termination Benefits
Restructuring Cost and Reserve [Line Items]
Restructuring and restructuring-related asset impairment charges, net	(886)	6,367	6,484	13,365
Restructuring/Asset impairment charges, net			6,484
Asset Impairment/Disposal of Assets
Restructuring Cost and Reserve [Line Items]
Restructuring and restructuring-related asset impairment charges, net	537	1,381	3,627	6,482
Restructuring/Asset impairment charges, net			3,627
Other Costs
Restructuring Cost and Reserve [Line Items]
Restructuring and restructuring-related asset impairment charges, net	$ 2,282	$ 2,004	6,955	$ 3,486
Restructuring/Asset impairment charges, net			$ 6,955

The charge against earnings resulting from the write down of long lived assets other than goodwill due to the difference between the carrying value and lower fair value.

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