v3.26.1
Contents Of Significant Accounts - Summary of Assumptions Used for Compensation Cost for These Market Conditions Was Measured at Fair Value Initially by Using Monte Carlo Simulation on The Grant Date (Detail) - Two Thousand Twenty Four Plan [Member] - Restricted Stock Plan For Employees [Member]
 12 Months Ended
Dec. 31, 2025
yr
$ / shares
First Tranche [Member]  
Contents Of Significant Accounts [Line Items]  
Share price of measurement date (NT$/ per share) | $ / shares $ 44.6
Second Tranche [Member]  
Contents Of Significant Accounts [Line Items]  
Share price of measurement date (NT$/ per share) | $ / shares $ 47.2
Top of range [member] | First Tranche [Member]  
Contents Of Significant Accounts [Line Items]  
Expected volatility 34.32%
Expected life 4
Risk-free interest rate 1.46%
Top of range [member] | Second Tranche [Member]  
Contents Of Significant Accounts [Line Items]  
Expected volatility 28.65%
Expected life 4
Risk-free interest rate 1.23%
Bottom of range [member] | First Tranche [Member]  
Contents Of Significant Accounts [Line Items]  
Expected volatility 23.76%
Expected life 2
Risk-free interest rate 1.40%
Bottom of range [member] | Second Tranche [Member]  
Contents Of Significant Accounts [Line Items]  
Expected volatility 25.11%
Expected life 2
Risk-free interest rate 1.14%