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EXIT ACTIVITIES - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Facility Closing
Restructuring Cost and Reserve [Line Items]
Exit costs associated with restructuring	$ 22	$ 15	$ 57	$ 52
Expected costs associated with closures associated with severance activity	$ 21		21
Facility Closing \| CRB Mills \| Minimum
Restructuring Cost and Reserve [Line Items]
Incurred charges related to write-off of assets			21
Accelerated depreciation related to plant closure			20
Facility Closing \| CRB Mills \| Maximum
Restructuring Cost and Reserve [Line Items]
Incurred charges related to write-off of assets			25
Accelerated depreciation related to plant closure			21
Facility Closing \| Folding Carton Plant \| Minimum
Restructuring Cost and Reserve [Line Items]
Incurred charges related to write-off of assets			18
Accelerated depreciation related to plant closure			25
Facility Closing \| Folding Carton Plant \| Maximum
Restructuring Cost and Reserve [Line Items]
Incurred charges related to write-off of assets			20
Accelerated depreciation related to plant closure			27
Facility Closing \| Construction in Progress \| Folding Carton Plant
Restructuring Cost and Reserve [Line Items]
Accelerated depreciation related to plant closure			24
Start-Up Costs \| Minimum
Restructuring Cost and Reserve [Line Items]
Start-up charges			65
Start-Up Costs \| Maximum
Restructuring Cost and Reserve [Line Items]
Start-up charges			75
Start-Up Costs \| Construction in Progress
Restructuring Cost and Reserve [Line Items]
Start-up charges			46
Start-Up Costs \| Construction in Progress \| CRB Mills
Restructuring Cost and Reserve [Line Items]
Incurred charges related to write-off of assets			20
One-time Termination Benefits \| Folding Carton Plant
Restructuring Cost and Reserve [Line Items]
Incurred charges related to write-off of assets			$ 17