v3.26.1
Employee Benefits - Effect of Variation in Assumptions (Details) - MXN ($)
$ in Millions
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Disclosure of net defined benefit liability (asset) [line items]      
Percentage of reasonably possible decrease in actuarial assumption 1.00%    
Percentage of reasonably possible increase in actuarial assumption 1.00%    
Current Service Cost $ 1,067 $ 1,052 $ 910
Remeasurements of the Net Defined Benefit Liability 10,501 8,760  
Pension and Retirement Plans      
Disclosure of net defined benefit liability (asset) [line items]      
Remeasurements of the Net Defined Benefit Liability 6,247 5,428  
Seniority Premiums      
Disclosure of net defined benefit liability (asset) [line items]      
Remeasurements of the Net Defined Benefit Liability 3,533 2,846  
Post Retirement Medical Services      
Disclosure of net defined benefit liability (asset) [line items]      
Remeasurements of the Net Defined Benefit Liability 721 486  
Net benefit cost recognized in the consolidated statements of income      
Disclosure of net defined benefit liability (asset) [line items]      
Current Service Cost 1,113 929 866
(Gain) or Loss on Settlement or Curtailment 107 306 278
Net Interest on the Net Defined Benefit Liability 735 587 590
Net benefit cost recognized in the consolidated statements of income | Pension and Retirement Plans      
Disclosure of net defined benefit liability (asset) [line items]      
Current Service Cost 585 505 489
(Gain) or Loss on Settlement or Curtailment 90 254 243
Net Interest on the Net Defined Benefit Liability 407 339 367
Net benefit cost recognized in the consolidated statements of income | Seniority Premiums      
Disclosure of net defined benefit liability (asset) [line items]      
Current Service Cost 494 394 345
(Gain) or Loss on Settlement or Curtailment 9 27 21
Net Interest on the Net Defined Benefit Liability 278 200 178
Net benefit cost recognized in the consolidated statements of income | Post Retirement Medical Services      
Disclosure of net defined benefit liability (asset) [line items]      
Current Service Cost 34 30 32
(Gain) or Loss on Settlement or Curtailment 8 25 14
Net Interest on the Net Defined Benefit Liability 50 $ 48 $ 45
Net benefit cost recognized in the consolidated statements of income | Discount rate +1% | Actuarial assumption of discount rates      
Disclosure of net defined benefit liability (asset) [line items]      
Current Service Cost 1,109    
(Gain) or Loss on Settlement or Curtailment (93)    
Net Interest on the Net Defined Benefit Liability 628    
Net benefit cost recognized in the consolidated statements of income | Discount rate +1% | Actuarial assumption of discount rates | Pension and Retirement Plans      
Disclosure of net defined benefit liability (asset) [line items]      
Current Service Cost 627    
(Gain) or Loss on Settlement or Curtailment (80)    
Net Interest on the Net Defined Benefit Liability 342    
Net benefit cost recognized in the consolidated statements of income | Discount rate +1% | Actuarial assumption of discount rates | Seniority Premiums      
Disclosure of net defined benefit liability (asset) [line items]      
Current Service Cost 458    
(Gain) or Loss on Settlement or Curtailment (9)    
Net Interest on the Net Defined Benefit Liability 258    
Net benefit cost recognized in the consolidated statements of income | Discount rate +1% | Actuarial assumption of discount rates | Post Retirement Medical Services      
Disclosure of net defined benefit liability (asset) [line items]      
Current Service Cost 24    
(Gain) or Loss on Settlement or Curtailment (4)    
Net Interest on the Net Defined Benefit Liability 28    
Net benefit cost recognized in the consolidated statements of income | Discount rate +1% | Actuarial assumption of expected rates of salary increases      
Disclosure of net defined benefit liability (asset) [line items]      
Current Service Cost 1,212    
(Gain) or Loss on Settlement or Curtailment (107)    
Net Interest on the Net Defined Benefit Liability 756    
Net benefit cost recognized in the consolidated statements of income | Discount rate +1% | Actuarial assumption of expected rates of salary increases | Pension and Retirement Plans      
Disclosure of net defined benefit liability (asset) [line items]      
Current Service Cost 716    
(Gain) or Loss on Settlement or Curtailment (97)    
Net Interest on the Net Defined Benefit Liability 470    
Net benefit cost recognized in the consolidated statements of income | Discount rate +1% | Actuarial assumption of expected rates of salary increases | Seniority Premiums      
Disclosure of net defined benefit liability (asset) [line items]      
Current Service Cost 496    
(Gain) or Loss on Settlement or Curtailment (10)    
Net Interest on the Net Defined Benefit Liability 286    
Net benefit cost recognized in the consolidated statements of income | Discount rate +1% | Actuarial assumption of medical cost trend rates | Post Retirement Medical Services      
Disclosure of net defined benefit liability (asset) [line items]      
Current Service Cost 18    
(Gain) or Loss on Settlement or Curtailment (6)    
Net Interest on the Net Defined Benefit Liability 42    
Net benefit cost recognized in the consolidated statements of income | Discount rate -1% | Actuarial assumption of discount rates      
Disclosure of net defined benefit liability (asset) [line items]      
Current Service Cost 1,240    
(Gain) or Loss on Settlement or Curtailment (112)    
Net Interest on the Net Defined Benefit Liability 820    
Net benefit cost recognized in the consolidated statements of income | Discount rate -1% | Actuarial assumption of discount rates | Pension and Retirement Plans      
Disclosure of net defined benefit liability (asset) [line items]      
Current Service Cost 697    
(Gain) or Loss on Settlement or Curtailment (96)    
Net Interest on the Net Defined Benefit Liability 478    
Net benefit cost recognized in the consolidated statements of income | Discount rate -1% | Actuarial assumption of discount rates | Seniority Premiums      
Disclosure of net defined benefit liability (asset) [line items]      
Current Service Cost 508    
(Gain) or Loss on Settlement or Curtailment (10)    
Net Interest on the Net Defined Benefit Liability 300    
Net benefit cost recognized in the consolidated statements of income | Discount rate -1% | Actuarial assumption of discount rates | Post Retirement Medical Services      
Disclosure of net defined benefit liability (asset) [line items]      
Current Service Cost 35    
(Gain) or Loss on Settlement or Curtailment (6)    
Net Interest on the Net Defined Benefit Liability 42    
Net benefit cost recognized in the consolidated statements of income | Discount rate -1% | Actuarial assumption of expected rates of salary increases      
Disclosure of net defined benefit liability (asset) [line items]      
Current Service Cost 1,084    
(Gain) or Loss on Settlement or Curtailment (89)    
Net Interest on the Net Defined Benefit Liability 632    
Net benefit cost recognized in the consolidated statements of income | Discount rate -1% | Actuarial assumption of expected rates of salary increases | Pension and Retirement Plans      
Disclosure of net defined benefit liability (asset) [line items]      
Current Service Cost 622    
(Gain) or Loss on Settlement or Curtailment (80)    
Net Interest on the Net Defined Benefit Liability 364    
Net benefit cost recognized in the consolidated statements of income | Discount rate -1% | Actuarial assumption of expected rates of salary increases | Seniority Premiums      
Disclosure of net defined benefit liability (asset) [line items]      
Current Service Cost 462    
(Gain) or Loss on Settlement or Curtailment (9)    
Net Interest on the Net Defined Benefit Liability 268    
Net benefit cost recognized in the consolidated statements of income | Discount rate -1% | Actuarial assumption of medical cost trend rates | Post Retirement Medical Services      
Disclosure of net defined benefit liability (asset) [line items]      
Current Service Cost 12    
(Gain) or Loss on Settlement or Curtailment (4)    
Net Interest on the Net Defined Benefit Liability 29    
Net benefit cost recognized in consolidated statements of other comprehensive income | Discount rate +1% | Actuarial assumption of discount rates      
Disclosure of net defined benefit liability (asset) [line items]      
Remeasurements of the Net Defined Benefit Liability 4,161    
Net benefit cost recognized in consolidated statements of other comprehensive income | Discount rate +1% | Actuarial assumption of discount rates | Pension and Retirement Plans      
Disclosure of net defined benefit liability (asset) [line items]      
Remeasurements of the Net Defined Benefit Liability 3,309    
Net benefit cost recognized in consolidated statements of other comprehensive income | Discount rate +1% | Actuarial assumption of discount rates | Seniority Premiums      
Disclosure of net defined benefit liability (asset) [line items]      
Remeasurements of the Net Defined Benefit Liability 735    
Net benefit cost recognized in consolidated statements of other comprehensive income | Discount rate +1% | Actuarial assumption of discount rates | Post Retirement Medical Services      
Disclosure of net defined benefit liability (asset) [line items]      
Remeasurements of the Net Defined Benefit Liability 117    
Net benefit cost recognized in consolidated statements of other comprehensive income | Discount rate +1% | Actuarial assumption of expected rates of salary increases      
Disclosure of net defined benefit liability (asset) [line items]      
Remeasurements of the Net Defined Benefit Liability 4,489    
Net benefit cost recognized in consolidated statements of other comprehensive income | Discount rate +1% | Actuarial assumption of expected rates of salary increases | Pension and Retirement Plans      
Disclosure of net defined benefit liability (asset) [line items]      
Remeasurements of the Net Defined Benefit Liability 3,676    
Net benefit cost recognized in consolidated statements of other comprehensive income | Discount rate +1% | Actuarial assumption of expected rates of salary increases | Seniority Premiums      
Disclosure of net defined benefit liability (asset) [line items]      
Remeasurements of the Net Defined Benefit Liability 813    
Net benefit cost recognized in consolidated statements of other comprehensive income | Discount rate +1% | Actuarial assumption of medical cost trend rates | Post Retirement Medical Services      
Disclosure of net defined benefit liability (asset) [line items]      
Remeasurements of the Net Defined Benefit Liability 145    
Net benefit cost recognized in consolidated statements of other comprehensive income | Discount rate -1% | Actuarial assumption of discount rates      
Disclosure of net defined benefit liability (asset) [line items]      
Remeasurements of the Net Defined Benefit Liability 4,800    
Net benefit cost recognized in consolidated statements of other comprehensive income | Discount rate -1% | Actuarial assumption of discount rates | Pension and Retirement Plans      
Disclosure of net defined benefit liability (asset) [line items]      
Remeasurements of the Net Defined Benefit Liability 3,787    
Net benefit cost recognized in consolidated statements of other comprehensive income | Discount rate -1% | Actuarial assumption of discount rates | Seniority Premiums      
Disclosure of net defined benefit liability (asset) [line items]      
Remeasurements of the Net Defined Benefit Liability 868    
Net benefit cost recognized in consolidated statements of other comprehensive income | Discount rate -1% | Actuarial assumption of discount rates | Post Retirement Medical Services      
Disclosure of net defined benefit liability (asset) [line items]      
Remeasurements of the Net Defined Benefit Liability 145    
Net benefit cost recognized in consolidated statements of other comprehensive income | Discount rate -1% | Actuarial assumption of expected rates of salary increases      
Disclosure of net defined benefit liability (asset) [line items]      
Remeasurements of the Net Defined Benefit Liability 4,131    
Net benefit cost recognized in consolidated statements of other comprehensive income | Discount rate -1% | Actuarial assumption of expected rates of salary increases | Pension and Retirement Plans      
Disclosure of net defined benefit liability (asset) [line items]      
Remeasurements of the Net Defined Benefit Liability 3,353    
Net benefit cost recognized in consolidated statements of other comprehensive income | Discount rate -1% | Actuarial assumption of expected rates of salary increases | Seniority Premiums      
Disclosure of net defined benefit liability (asset) [line items]      
Remeasurements of the Net Defined Benefit Liability 778    
Net benefit cost recognized in consolidated statements of other comprehensive income | Discount rate -1% | Actuarial assumption of medical cost trend rates | Post Retirement Medical Services      
Disclosure of net defined benefit liability (asset) [line items]      
Remeasurements of the Net Defined Benefit Liability $ 116