v3.25.4
Employee compensation and benefits - Benefits expected to be paid from plans (Details) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Disclosure of defined benefit plans [line items]    
Estimate of contributions expected to be paid to plan for next annual reporting period $ 109  
Principal plan    
Disclosure of defined benefit plans [line items]    
Estimate of contributions expected to be paid to plan for next annual reporting period $ 0  
Weighted average duration of defined benefit obligation 11 years 4 months 24 days 11 years 9 months 18 days
Other plans    
Disclosure of defined benefit plans [line items]    
Estimate of contributions expected to be paid to plan for next annual reporting period $ 109  
Weighted average duration of defined benefit obligation 9 years 8 months 12 days 9 years 9 months 18 days
Pension Plan | Principal plan | 2026    
Disclosure of defined benefit plans [line items]    
Benefits expected to be paid from plans $ 1,170  
Pension Plan | Principal plan | 2027    
Disclosure of defined benefit plans [line items]    
Benefits expected to be paid from plans 1,203  
Pension Plan | Principal plan | 2028    
Disclosure of defined benefit plans [line items]    
Benefits expected to be paid from plans 1,239  
Pension Plan | Principal plan | 2029    
Disclosure of defined benefit plans [line items]    
Benefits expected to be paid from plans 1,275  
Pension Plan | Principal plan | 2030    
Disclosure of defined benefit plans [line items]    
Benefits expected to be paid from plans 1,313  
Pension Plan | Principal plan | 2031-2035    
Disclosure of defined benefit plans [line items]    
Benefits expected to be paid from plans 7,175  
Pension Plan | Other plans | 2026    
Disclosure of defined benefit plans [line items]    
Benefits expected to be paid from plans 436  
Pension Plan | Other plans | 2027    
Disclosure of defined benefit plans [line items]    
Benefits expected to be paid from plans 436  
Pension Plan | Other plans | 2028    
Disclosure of defined benefit plans [line items]    
Benefits expected to be paid from plans 437  
Pension Plan | Other plans | 2029    
Disclosure of defined benefit plans [line items]    
Benefits expected to be paid from plans 433  
Pension Plan | Other plans | 2030    
Disclosure of defined benefit plans [line items]    
Benefits expected to be paid from plans 437  
Pension Plan | Other plans | 2031-2035    
Disclosure of defined benefit plans [line items]    
Benefits expected to be paid from plans $ 2,259