v3.26.1
Payroll, staff and employee benefits obligations - Change in benefit obligations and plan assets (Details) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Euro zone      
Change in benefit obligations and plan assets      
Contribution for the net pension liability in the balance sheet (as a percent) 79.00%    
United Kingdom      
Change in benefit obligations and plan assets      
Contribution for the net pension liability in the balance sheet (as a percent) 2.00%    
United States      
Change in benefit obligations and plan assets      
Contribution for the net pension liability in the balance sheet (as a percent) 8.00%    
Pension benefits      
Change in benefit obligations and plan assets      
Balance at beginning of year $ 1,136 $ 1,123  
Balance at year-end 1,241 1,136 $ 1,123
(FUNDED) UNFUNDED STATUS 1,184 1,103 1,079
Pension benefits and other benefits liabilities 1,529 1,290 1,453
Other non-current assets (288) (154) (330)
Pension benefits | United Kingdom      
Change in benefit obligations and plan assets      
Actuarial losses / (gains)   147  
Pension benefits | Benefit obligation      
Change in benefit obligations and plan assets      
Balance at beginning of year 8,176 8,847 8,267
Current service cost 212 191 178
Interest cost (income) 369 328 355
Past service cost (32) 60 47
Settlements 2 (55) 2
Plan participants' contributions 28 26 23
Benefits paid (635) (538) (563)
Actuarial losses / (gains) 12 (277) 393
Foreign currency translation and other 799 (406) 146
Balance at year-end 8,931 8,176 8,847
Pension benefits | Benefit obligation | Plans entirely or partially funded      
Change in benefit obligations and plan assets      
Balance at beginning of year 7,689 8,392  
Balance at year-end 8,268 7,689 8,392
Pension benefits | Benefit obligation | Plans not funded      
Change in benefit obligations and plan assets      
Balance at beginning of year 487 455  
Balance at year-end 663 487 455
Pension benefits | Plan assets      
Change in benefit obligations and plan assets      
Balance at beginning of year (7,073) (7,768) (7,306)
Interest cost (income) (332) (313) (332)
Settlements   57  
Plan participants' contributions (28) (26) (23)
Employer contributions (181) (163) (254)
Benefits paid 578 497 523
Actuarial losses / (gains) (19) 288 (272)
Foreign currency translation and other (692) 355 (104)
Balance at year-end (7,747) (7,073) (7,768)
Effect of asset ceiling (14)    
Pension benefits | Asset ceiling      
Change in benefit obligations and plan assets      
Balance at beginning of year 33 44  
Balance at year-end 57 33 44
Other benefits      
Change in benefit obligations and plan assets      
Balance at beginning of year 411 468  
Balance at year-end 423 411 468
(FUNDED) UNFUNDED STATUS 423 411 468
Pension benefits and other benefits liabilities 423 411 468
Other benefits | Benefit obligation      
Change in benefit obligations and plan assets      
Balance at beginning of year 411 468 467
Current service cost 10 8 12
Interest cost (income) 16 19 20
Past service cost   0  
Benefits paid (22) (26) (24)
Actuarial losses / (gains) (35) (30) (6)
Foreign currency translation and other 43 (28) (1)
Balance at year-end 423 411 468
Other benefits | Benefit obligation | Plans not funded      
Change in benefit obligations and plan assets      
Balance at beginning of year 411 468  
Balance at year-end $ 423 $ 411 $ 468