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General Information - Business Combinations, Exit Activities and Other Special Items, Net (Details) - USD ($) $ in Millions	3 Months Ended				6 Months Ended
	Jun. 30, 2026	Mar. 31, 2026	Dec. 31, 2025	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Business Combination, Pro Forma Information [Line Items]
Current liabilities held-for-sale	$ 2		$ 0		$ 2
Multiple Packaging Facilities
Business Combination, Pro Forma Information [Line Items]
Current asset held-for-sale			10
Gain on sale of exited property	1				5
Multiple Packaging Facilities \| Discontinued Operations, Disposed of by Sale \| Croatia Business
Business Combination, Pro Forma Information [Line Items]
Total consideration	6				6
Charges to adjust held for sale assets to estimated fair value					13
Current asset held-for-sale	8				8
Current liabilities held-for-sale	2				2
Facility Closing
Business Combination, Pro Forma Information [Line Items]
Exit activities	$ 5		6		23
Start-Up Costs
Business Combination, Pro Forma Information [Line Items]
Exit activities			$ 55	$ 10	$ 0	$ 17
Kalamazoo, Michigan and Texarkana, Texas \| Discontinued Project
Business Combination, Pro Forma Information [Line Items]
Exit activities		$ 40