v3.26.1
Employee benefits (Details 8) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Country of domicile [member]    
IfrsStatementLineItems [Line Items]    
Actuarial assumption of medical cost trend rates 5.99% 6.61%
Actuarial assumption of ultimate medical cost trend rates 5.99% 6.61%
Country of domicile [member] | Actuarial assumption of discount rates [member]    
IfrsStatementLineItems [Line Items]    
Increase (decrease) in defined benefit obligation due to reasonably possible increase in actuarial assumption $ 2,765  
Actuarial Assumption Of Discount Rate, Increase In Assumption 11.98%  
Increase (decrease) in defined benefit obligation due to reasonably possible decrease in actuarial assumption $ 3,064  
Actuarial Assumption Of Discount Rate, Decrease In Assumption 9.81%  
Country of domicile [member] | Bottom of range [member]    
IfrsStatementLineItems [Line Items]    
Actuarial assumption of discount rates 10.27% 11.07%
Actuarial assumption of nominal average rate of expense or income 10.38% 11.07%
Actuarial assumption of expected rates of salary increases 2.90% 3.50%
Actuarial assumption of expected rates of pension increases 3.41% 3.50%
Actuarial assumption of expected rates of inflation 2.90% 3.50%
Country of domicile [member] | Top of range [member]    
IfrsStatementLineItems [Line Items]    
Actuarial assumption of discount rates 11.70% 12.12%
Actuarial assumption of nominal average rate of expense or income 11.70% 12.12%
Actuarial assumption of expected rates of salary increases 5.57% 5.57%
Actuarial assumption of expected rates of pension increases 4.00% 4.25%
Actuarial assumption of expected rates of inflation 4.00% 4.25%
Foreign countries [member]    
IfrsStatementLineItems [Line Items]    
Actuarial assumption of nominal average rate of expense or income   4.61%
Actuarial assumption of expected rates of salary increases 3.00% 3.10%
Actuarial assumption of expected rates of pension increases 3.00% 3.00%
Actuarial assumption of medical cost trend rates 4.50% 4.50%
Actuarial assumption of ultimate medical cost trend rates 4.50% 4.39%
Actuarial assumption of expected rates of inflation 2.06% 2.08%
Foreign countries [member] | Actuarial assumption of discount rates [member]    
IfrsStatementLineItems [Line Items]    
Increase (decrease) in defined benefit obligation due to reasonably possible increase in actuarial assumption $ 2,474  
Actuarial Assumption Of Discount Rate, Increase In Assumption 5.87%  
Increase (decrease) in defined benefit obligation due to reasonably possible decrease in actuarial assumption $ 3,108  
Actuarial Assumption Of Discount Rate, Decrease In Assumption 3.87%  
Foreign countries [member] | Bottom of range [member]    
IfrsStatementLineItems [Line Items]    
Actuarial assumption of discount rates 4.85% 4.66%
Actuarial assumption of nominal average rate of expense or income 4.66%  
Foreign countries [member] | Top of range [member]    
IfrsStatementLineItems [Line Items]    
Actuarial assumption of discount rates 4.90% 4.72%
Actuarial assumption of nominal average rate of expense or income 4.72%