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v3.25.1

Income Tax Expense - Details of Deferred Tax Assets (Liabilities) (Detail) $ in Thousands, $ in Thousands | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2024 TWD ($) | Dec. 31, 2023 TWD ($) | Dec. 31, 2022 TWD ($) | Dec. 31, 2024 USD ($) | Dec. 31, 2021 TWD ($)
Disclosure of the detail of deferred tax assets and liabilities [line items] |  |  |  |  |
Deferred tax assets | $ 126,213 | $ 163,282 | $ 159,286 | $ 3,849 | $ 180,598
Deferred tax liabilities | (93,310) | (127,193) | (201,741) | $ (2,846) | $ (278,177)
Deferred tax assets unrealized loss on inventories [member] |  |  |  |  |
Disclosure of the detail of deferred tax assets and liabilities [line items] |  |  |  |  |
Beginning balance | 37,253 | 21,126 | 24,317 |  |
Recognized in profit or loss | (5,223) | 16,127 | (3,191) |  |
Ending balance | 32,030 | 37,253 | 21,126 |  |
Property, plant and equipment, deferred tax assets [member] |  |  |  |  |
Disclosure of the detail of deferred tax assets and liabilities [line items] |  |  |  |  |
Beginning balance | 40,741 | 38,894 | 36,636 |  |
Ending balance | 42,452 | 40,741 | 38,894 |  |
Provisions [member] |  |  |  |  |
Disclosure of the detail of deferred tax assets and liabilities [line items] |  |  |  |  |
Beginning balance | 14,377 | 12,859 | 2,849 |  |
Recognized in profit or loss | (10) | 1,518 | 10,010 |  |
Ending balance | 14,367 | 14,377 | 12,859 |  |
Deferred tax assets deferred revenue [member] |  |  |  |  |
Disclosure of the detail of deferred tax assets and liabilities [line items] |  |  |  |  |
Beginning balance | 1,626 | 8,132 | 14,638 |  |
Recognized in profit or loss | (1,626) | (6,506) | (6,506) |  |
Ending balance |  | 1,626 | 8,132 |  |
Net defined benefit liability [member] |  |  |  |  |
Disclosure of the detail of deferred tax assets and liabilities [line items] |  |  |  |  |
Beginning balance | 42,057 | 48,433 | 97,248 |  |
Recognized in profit or loss | (4,879) | (4,236) | (4,368) |  |
Recognized in other comprehensive income | (11,261) | (2,140) | (44,447) |  |
Ending balance | 25,917 | 42,057 | 48,433 |  |
Unrealized Exchange Gains Losses Deferred Tax Assets [Member] |  |  |  |  |
Disclosure of the detail of deferred tax assets and liabilities [line items] |  |  |  |  |
Beginning balance | 18,185 | 24,217 | 2,161 |  |
Recognized in profit or loss | (18,185) | (6,032) | 22,056 |  |
Ending balance |  | 18,185 | 24,217 |  |
Others [member] |  |  |  |  |
Disclosure of the detail of deferred tax assets and liabilities [line items] |  |  |  |  |
Beginning balance | 9,043 | 5,625 | 2,749 |  |
Recognized in profit or loss | 2,404 | 3,418 | 2,876 |  |
Ending balance | 11,447 | 9,043 | 5,625 |  |
Deferred tax asset [member] |  |  |  |  |
Disclosure of the detail of deferred tax assets and liabilities [line items] |  |  |  |  |
Beginning balance | 163,282 | 159,286 | 180,598 |  |
Recognized in profit or loss | (25,808) | 6,136 | 23,135 |  |
Recognized in other comprehensive income | (11,261) | (2,140) | (44,447) |  |
Ending balance | 126,213 | 163,282 | 159,286 |  |
Property, plant and equipment, deferred tax liabilities [member] |  |  |  |  |
Disclosure of the detail of deferred tax assets and liabilities [line items] |  |  |  |  |
Beginning balance | (74,832) | (116,974) | (192,687) |  |
Recognized in profit or loss | 9,086 | 42,142 | 75,713 |  |
Ending balance | (65,746) | (74,832) | (116,974) |  |
Unrealized exchange gains losses deferred tax liabilities [member] |  |  |  |  |
Disclosure of the detail of deferred tax assets and liabilities [line items] |  |  |  |  |
Recognized in profit or loss | (9,810) |  |  |  |
Ending balance | (9,810) |  |  |  |
Property, plant and equipment [member] |  |  |  |  |
Disclosure of the detail of deferred tax assets and liabilities [line items] |  |  |  |  |
Recognized in profit or loss | 1,711 | 1,847 | 2,258 |  |
Financial assets at fair value through other comprehensive income [member] |  |  |  |  |
Disclosure of the detail of deferred tax assets and liabilities [line items] |  |  |  |  |
Beginning balance | (21,205) | (72,843) | (85,402) |  |
Recognized in other comprehensive income | 3,458 | 51,638 | 12,559 |  |
Ending balance | (17,747) | (21,205) | (72,843) |  |
Gain on investment in associates [member] |  |  |  |  |
Disclosure of the detail of deferred tax assets and liabilities [line items] |  |  |  |  |
Beginning balance | (31,151) | (11,923) |  |  |
Recognized in profit or loss | 31,151 | (19,228) | (11,923) |  |
Ending balance |  | (31,151) | (11,923) |  |
Others [member] |  |  |  |  |
Disclosure of the detail of deferred tax assets and liabilities [line items] |  |  |  |  |
Beginning balance | (5) | (1) | (88) |  |
Recognized in profit or loss | (2) | (4) | 87 |  |
Ending balance | (7) | (5) | (1) |  |
Deferred tax liabilities [member] |  |  |  |  |
Disclosure of the detail of deferred tax assets and liabilities [line items] |  |  |  |  |
Beginning balance | (127,193) | (201,741) | (278,177) |  |
Recognized in profit or loss | 30,425 | 22,910 | 63,877 |  |
Recognized in other comprehensive income | 3,458 | 51,638 | 12,559 |  |
Ending balance | $ (93,310) | $ (127,193) | $ (201,741) |  |

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