v3.26.1
Accumulated other comprehensive loss - Schedule of AOCI (Details) - USD ($)
$ in Millions
 3 Months Ended 6 Months Ended 12 Months Ended
Jun. 30, 2026
Mar. 31, 2026
Jun. 30, 2025
Mar. 31, 2025
Jun. 30, 2026
Jun. 30, 2025
Dec. 31, 2025
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]              
Beginning balance $ 12,966 $ 13,121 $ 9,607 $ 9,779 $ 13,121 $ 9,779 $ 9,779
Total other comprehensive income (loss), net of tax (100) (53) 220 23 (153) 243 213
Ending balance 12,858 12,966 12,272 9,607 12,858 12,272 13,121
Foreign Currency Translation Adjustment              
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]              
Beginning balance (484) (420) (607) (623) (420) (623) (623)
Other comprehensive income (loss) before reclassifications (94)   222   (158) 238  
Amounts reclassified from Accumulated other comprehensive loss to Net income 0   0   0 0  
Total other comprehensive income (loss), net of tax (94)   222   (158) 238  
Unrecognized gain transferred from Holcim pension     0     0  
Ending balance (578) (484) (385) (607) (578) (385) (420)
Cash Flow Hedges              
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]              
Beginning balance 12 (1) 1 (7) (1) (7) (7)
Other comprehensive income (loss) before reclassifications (11)   1   0 10  
Amounts reclassified from Accumulated other comprehensive loss to Net income 6   (2)   8 (3)  
Total other comprehensive income (loss), net of tax (5)   (1)   8 7  
Unrecognized gain transferred from Holcim pension     0     0  
Ending balance 7 12 0 1 7 0 (1)
Defined Benefit Pension Plans and Other Postretirement Benefit Plans              
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]              
Beginning balance 39 41 34 35 41 35 35
Other comprehensive income (loss) before reclassifications 0   0   0 0  
Amounts reclassified from Accumulated other comprehensive loss to Net income (1)   (1)   (3) (2)  
Total other comprehensive income (loss), net of tax (1)   (1)   (3) (2)  
Unrecognized gain transferred from Holcim pension     2     2  
Ending balance 38 39 35 34 38 35 41
Total              
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]              
Beginning balance (433) (380) (572) (595) (380) (595) (595)
Other comprehensive income (loss) before reclassifications (105)   223   (158) 248  
Amounts reclassified from Accumulated other comprehensive loss to Net income 5   (3)   5 (5)  
Total other comprehensive income (loss), net of tax (100) (53) 220 23 (153) 243 213
Unrecognized gain transferred from Holcim pension     2     2  
Ending balance $ (533) $ (433) $ (350) $ (572) $ (533) $ (350) $ (380)