v3.26.1
ACQUISITIONS - Narrative (Details)
$ / shares in Units, € in Millions, $ in Millions
3 Months Ended 12 Months Ended
Jun. 30, 2025
USD ($)
Jun. 30, 2025
EUR (€)
Jan. 31, 2025
USD ($)
plant
$ / shares
shares
Mar. 31, 2025
USD ($)
Dec. 31, 2025
USD ($)
Disposal Group, Disposed of by Sale, Not Discontinued Operations | European Plants          
Business Combination [Line Items]          
Number of plants divested | plant     5    
Proceeds from divestiture of businesses $ 147 € 125      
Gain on disposition of business         $ 46
DS Smith Plc          
Business Combination [Line Items]          
Number of IP shares issued for each DS Smith share (in shares) | shares     0.1285    
Business combination, consideration transferred, equity interest, share issued, number of shares (in shares) | shares     178,126,631    
Business combination, voting equity interest acquired, percentage     34.10%    
Business combination, price per share (in dollars per share) | $ / shares     $ 55.63    
Business combination, consideration transferred     $ 9,900    
Business combination, acquisition-related cost, expense       $ 87  
Business combination, acquiree's revenue since acquisition date, actual       1,300  
Business combination, acquiree's earnings (loss) since acquisition date, actual       (107)  
Business combination, pro forma information, pro forma income (loss), after tax       (107)  
DS Smith Plc | Additional Amortization Expense on Identifiable Assets          
Business Combination [Line Items]          
Business combination, pro forma information, pro forma income (loss), after tax       9  
DS Smith Plc | Additional Depreciation Expense On Fixed Assets          
Business Combination [Line Items]          
Business combination, pro forma information, pro forma income (loss), after tax       6  
DS Smith Plc | Business Combination, Pro Forma Information, Nonrecurring Adjustment, Inventory, Fair Value Adjustment          
Business Combination [Line Items]          
Business combination, pro forma information, pro forma income (loss), after tax       70  
DS Smith Plc | Business Combination, Pro Forma Information, Nonrecurring Adjustment, Acquisition-Related Cost          
Business Combination [Line Items]          
Business combination, integration-related cost, expense       $ 65