Retirement Benefit Plans - Summary of Sensitivity Analysis on Defined Obligations (Detail) $ in Thousands, $ in Thousands |
Dec. 31, 2023
TWD ($)
|
Dec. 31, 2023
USD ($)
|
Dec. 31, 2022
TWD ($)
|
|---|---|---|---|
| Actuarial assumption of discount rates [member] | |||
| Disclosure of sensitivity analysis for actuarial assumptions [line items] | |||
| Change in defined obligation due to increase in actuarial assumption | $ (421,758) | $ (13,774) | $ (437,529) |
| Change in defined obligation due to decrease in actuarial assumption | 455,520 | 14,877 | 472,595 |
| Actuarial assumption of expected rates of salary increases [member] | |||
| Disclosure of sensitivity analysis for actuarial assumptions [line items] | |||
| Change in defined obligation due to increase in actuarial assumption | 425,080 | 13,882 | 444,815 |
| Change in defined obligation due to decrease in actuarial assumption | $ (397,988) | $ (12,998) | $ (416,488) |