Contents of Significant Accounts - Defined Benefit Plan Recognized on the Consolidated Balance Sheets (Detail) $ in Thousands, $ in Thousands |
Dec. 31, 2025
TWD ($)
|
Dec. 31, 2025
USD ($)
|
Dec. 31, 2024
TWD ($)
|
|---|---|---|---|
| Disclosure Of Defined Benefit Plans [Abstract] | |||
| Present value of the defined benefit obligation | $ (4,250,522) | $ (4,392,723) | |
| Fair value of plan assets | 3,384,303 | 2,960,474 | |
| Funded status | (866,219) | (1,432,249) | |
| Net defined benefit liabilities, noncurrent recognized on the consolidated balance sheets | $ (866,219) | $ (27,613) | $ (1,432,249) |