v3.25.2
Accumulated Other Comprehensive Loss - Schedule of Accumulated Other Comprehensive Income (Loss) (Details) - USD ($)
$ in Millions
 3 Months Ended 6 Months Ended
Jun. 30, 2025
Jun. 30, 2024
Jun. 30, 2025
Jun. 30, 2024
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]        
Beginning balance $ (17,889) $ (6,249) [1] $ (17,387) $ (6,174) [2]
Other comprehensive loss (income) (651) 121 (1,018) 224
Ending balance (18,324) (5,941) (18,324) (5,941)
Total        
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]        
Beginning balance 1,079 950 [1] 1,446 847 [2]
Other comprehensive loss (income) (651) 121 (1,018) 224
Ending balance 428 1,071 428 1,071
Foreign Currency Translation        
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]        
Beginning balance 1,306 905 1,684 789
Other comprehensive loss (income) (712) 151 (1,090) 267
Ending balance 594 1,056 594 1,056
Cash Flow Hedges        
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]        
Beginning balance 13 19 16 16
Other comprehensive loss (income) 5 (6) 2 (3)
Ending balance 18 13 18 13
Defined Benefit Pension and Postretirement Plans        
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]        
Beginning balance 511 777 497 793
Other comprehensive loss (income) 56 (24) 70 (40)
Ending balance 567 753 567 753
Other Reserves        
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]        
Beginning balance (751) (751) (751) (751)
Other comprehensive loss (income) 0 0 0 0
Ending balance $ (751) $ (751) $ (751) $ (751)
[1] Pursuant to the Transaction Agreement, on July 5, 2024 each issued ordinary share, par value €0.001 per share, of Smurfit Kappa (a “Smurfit Kappa Share”) was exchanged for
one ordinary share, par value $0.001 per share, of Smurfit Westrock (a “Smurfit Westrock Share”). The exchange of shares is reflected retroactively to the earliest period
presented.
[2] Pursuant to the Transaction Agreement, on July 5, 2024 each issued ordinary share, par value €0.001 per share, of Smurfit Kappa (a “Smurfit Kappa Share”) was exchanged for
one ordinary share, par value $0.001 per share, of Smurfit Westrock (a “Smurfit Westrock Share”). The exchange of shares is reflected retroactively to the earliest period
presented.