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	9 Months Ended
Sep. 28, 2025	Sep. 29, 2024	Sep. 28, 2025	Sep. 29, 2024
Restructuring Cost and Reserve [Line Items]
Restructuring and restructuring-related asset impairment charges	$ 48,388	$ 6,149	$ 71,721	$ 55,122
Other asset impairments	0	0	0	0
Restructuring/Asset impairment charges	48,388	6,149	71,721	55,122
Operating Segments \| Consumer Packaging
Restructuring Cost and Reserve [Line Items]
Restructuring and restructuring-related asset impairment charges	34,885	2,468	37,623	16,661
Operating Segments \| Industrial Paper Packaging
Restructuring Cost and Reserve [Line Items]
Restructuring and restructuring-related asset impairment charges	11,323	3,798	32,092	34,138
All Other
Restructuring Cost and Reserve [Line Items]
Restructuring and restructuring-related asset impairment charges	0	0	(16)	1,362
Corporate
Restructuring Cost and Reserve [Line Items]
Restructuring and restructuring-related asset impairment charges	2,180	(117)	2,022	2,961
Severance and Termination Benefits
Restructuring Cost and Reserve [Line Items]
Restructuring and restructuring-related asset impairment charges	37,865	1,378	51,230	24,649
Restructuring/Asset impairment charges			51,230
Asset Impairment/Disposal of Assets
Restructuring Cost and Reserve [Line Items]
Restructuring and restructuring-related asset impairment charges	5,074	2,268	11,556	21,288
Restructuring/Asset impairment charges			11,556
Other Costs
Restructuring Cost and Reserve [Line Items]
Restructuring and restructuring-related asset impairment charges	$ 5,449	$ 2,503	8,935	$ 9,185
Restructuring/Asset impairment charges			$ 8,935

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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