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Capital stock - Additional Information (Detail) $ / shares in Units, $ in Thousands, $ in Thousands | 12 Months Ended |  |  |
--- | --- | --- | --- | ---
Dec. 31, 2024 TWD ($) $ / shares shares | Dec. 31, 2024 USD ($) shares | Dec. 31, 2023 TWD ($) shares | Dec. 31, 2022 shares
Disclosure of classes of share capital [line items] |  |  |  |
Ordinary shares par value | $ / shares | $ 10 |  |  |
Number of shares outstanding | 727,240,000 | 727,240,000 | 727,240,000 | 727,240,000
Authorised capital | $ | $ 9,700,000 |  |  |
Number of shares authorized | 970,000,000 | 970,000,000 |  |
Paid in capital | $ 7,272,401 | $ 221,787 | $ 7,272,401 |
Ordinary shares [member] |  |  |  |
Disclosure of classes of share capital [line items] |  |  |  |
Number of shares outstanding | 74,548,000 | 74,548,000 |  |
American depositary shares [member] |  |  |  |
Disclosure of classes of share capital [line items] |  |  |  |
Number of shares represented by each unit of ADS | 20 |  |  |
Number of shares outstanding | 3,727,383,000 | 3,727,383,000 |  |

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