Income Tax - Summary of Income Tax Recognized in Other Comprehensive Income (Detail) $ in Thousands, $ in Thousands |
12 Months Ended | |||
|---|---|---|---|---|
|
Dec. 31, 2023
TWD ($)
|
Dec. 31, 2023
USD ($)
|
Dec. 31, 2022
TWD ($)
|
Dec. 31, 2021
TWD ($)
|
|
| Income tax relating to components of other comprehensive income [abstract] | ||||
| Deferred income tax Related to remeasurement of defined benefit plans | $ (2,214) | $ (72) | $ (208,482) | $ (19,319) |
| Unrealized gain (loss) on equity instruments at fair value through other comprehensive income | (262,404) | (8,570) | 370,091 | (160,084) |
| Income tax relating to investments in Debt instruments included in other comprehensive income | (5,792) | (189) | 0 | 0 |
| Income tax recognized in other comprehensive income | $ (270,410) | $ (8,831) | $ 161,609 | $ (179,403) |