v3.26.1
Employee Benefits - Summary of Amounts and Types of Plan Assets (Detail) - MXN ($)
$ in Thousands
12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Disclosure of defined benefit plans [line items]      
Cash and cash equivalents $ 2,506,395 $ 113,020  
Debt instruments 2,243,958 2,080,727  
Changes in Defined Benefit Obligations (DBO)      
Defined benefit obligations at the beginning of the year 1,232,589,895    
Service costs 25,203,473 23,112,133  
Change in financial assumptions 184,295,367 (253,363,361)  
Change in demographic assumptions 3,949,508 15,407,718  
For experience during the year (13,045,339) 42,539,216  
Reductions (33,344) 0  
Defined benefit liabilities at end of year $ 1,470,059,563 $ 1,232,589,895  
Actuarial assumption of discount rates      
Changes in Defined Benefit Obligations (DBO)      
Percentage of increase in the assumed variation rate 9.95% 11.28%  
Plan Assets      
Disclosure of defined benefit plans [line items]      
Cash and cash equivalents $ 2,506,395 $ 113,020  
Debt instruments 2,243,958 2,080,727  
Total 4,750,353 2,193,747 $ 2,176,432
Changes in Defined Benefit Obligations (DBO)      
Defined benefit obligations at the beginning of the year 1,222,680,092 1,362,164,696  
Service costs 12,244,394 15,122,465  
Financing costs 132,434,039 123,578,683  
Past service costs 12,890,300 7,989,668  
Payments by the fund (93,127,900) (90,758,993)  
Defined benefit liabilities at end of year $ 1,462,287,117 $ 1,222,680,092