RESTRUCTURING CHARGES, NET - Restructuring and Related Costs (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Restructuring Cost and Reserve [Line Items]
Restructuring charges, net	$ 342	$ 55	$ 464	$ 58
Red River Mill
Restructuring Cost and Reserve [Line Items]
Restructuring charges, net	0		85
Severance costs			18
Inventory write-down			26
Other restructuring costs			41
Red River Mill | Inventories
Restructuring Cost and Reserve [Line Items]
Restructuring reserve	25		25
Red River Mill | Accrued Payroll and Benefits
Restructuring Cost and Reserve [Line Items]
Restructuring reserve	7		7
Red River Mill | Other Current And Other Noncurrent Liabilities
Restructuring Cost and Reserve [Line Items]
Restructuring reserve	36		36
Savannah Mill
Restructuring Cost and Reserve [Line Items]
Restructuring charges, net	135		135
Savannah Mill | Inventories
Restructuring Cost and Reserve [Line Items]
Restructuring reserve	38		38
Savannah Mill | Accrued Payroll and Benefits
Restructuring Cost and Reserve [Line Items]
Restructuring reserve	31		31
Savannah Mill | Other Current And Other Noncurrent Liabilities
Restructuring Cost and Reserve [Line Items]
Restructuring reserve	66		66
Riceboro Mill
Restructuring Cost and Reserve [Line Items]
Restructuring charges, net	95		95
Riceboro Mill | Inventories
Restructuring Cost and Reserve [Line Items]
Restructuring reserve	29		29
Riceboro Mill | Accrued Payroll and Benefits
Restructuring Cost and Reserve [Line Items]
Restructuring reserve	12		12
Riceboro Mill | Other Current And Other Noncurrent Liabilities
Restructuring Cost and Reserve [Line Items]
Restructuring reserve	54		54
Packaging Solutions EMEA
Restructuring Cost and Reserve [Line Items]
Restructuring charges, net	67		97
Other restructuring costs	67		97
Packaging Solutions EMEA | Accrued Payroll and Benefits
Restructuring Cost and Reserve [Line Items]
Restructuring reserve	79		79
Packaging Solutions EMEA | Other Current Liabilities
Restructuring Cost and Reserve [Line Items]
Restructuring reserve	11		11
Packaging Solutions North America
Restructuring Cost and Reserve [Line Items]
Restructuring charges, net	45		52
Other restructuring costs	45		52
Packaging Solutions North America | Accrued Payroll and Benefits
Restructuring Cost and Reserve [Line Items]
Restructuring reserve	$ 46		$ 46