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v3.22.1

Income Tax Expense - Details of Deferred Tax Assets (Liabilities) (Detail) $ in Thousands, $ in Thousands | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2021 TWD ($) | Dec. 31, 2020 TWD ($) | Dec. 31, 2019 TWD ($) | Dec. 31, 2021 USD ($) | Dec. 31, 2018 TWD ($)
Disclosure of the detail of deferred tax assets and liabilities [line items] |  |  |  |  |
Deferred tax assets | $ 180,598 | $ 185,691 | $ 194,552 | $ 6,510 | $ 226,716
Deferred tax liabilities | (278,177) | (310,427) | (309,129) | $ (10,028) | $ (308,759)
Deferred tax assets unrealized loss on inventories [member] |  |  |  |  |
Disclosure of the detail of deferred tax assets and liabilities [line items] |  |  |  |  |
Beginning balance | 15,963 | 12,700 | 7,232 |  |
Recognized in profit or loss | 8,354 | 3,263 | 5,468 |  |
Ending balance | 24,317 | 15,963 | 12,700 |  |
Property, plant and equipment, deferred tax assets [member] |  |  |  |  |
Disclosure of the detail of deferred tax assets and liabilities [line items] |  |  |  |  |
Beginning balance | 36,401 | 38,668 | 64,183 |  |
Recognized in profit or loss | 235 | (2,267) | (25,515) |  |
Ending balance | 36,636 | 36,401 | 38,668 |  |
Provisions [member] |  |  |  |  |
Disclosure of the detail of deferred tax assets and liabilities [line items] |  |  |  |  |
Beginning balance | 2,678 | 5,600 | 12,396 |  |
Recognized in profit or loss | 171 | (2,922) | (6,796) |  |
Ending balance | 2,849 | 2,678 | 5,600 |  |
Deferred tax assets deferred revenue [member] |  |  |  |  |
Disclosure of the detail of deferred tax assets and liabilities [line items] |  |  |  |  |
Beginning balance | 21,144 | 27,650 | 34,156 |  |
Recognized in profit or loss | (6,506) | (6,506) | (6,506) |  |
Ending balance | 14,638 | 21,144 | 27,650 |  |
Net defined benefit liability [member] |  |  |  |  |
Disclosure of the detail of deferred tax assets and liabilities [line items] |  |  |  |  |
Beginning balance | 98,921 | 92,612 | 100,743 |  |
Recognized in profit or loss | (4,672) | (4,089) | (3,948) |  |
Recognized in other comprehensive income | 2,999 | 10,398 | (4,183) |  |
Ending balance | 97,248 | 98,921 | 92,612 |  |
Unrealized exchange losses deferred tax assets [member] |  |  |  |  |
Disclosure of the detail of deferred tax assets and liabilities [line items] |  |  |  |  |
Beginning balance | 9,915 | 17,296 | 3,575 |  |
Recognized in profit or loss | (7,754) | (7,381) | 13,721 |  |
Ending balance | 2,161 | 9,915 | 17,296 |  |
Investment tax credit [member] |  |  |  |  |
Disclosure of the detail of deferred tax assets and liabilities [line items] |  |  |  |  |
Beginning balance |  |  | 4,420 |  |
Recognized in profit or loss |  |  | (4,420) |  |
Others [member] |  |  |  |  |
Disclosure of the detail of deferred tax assets and liabilities [line items] |  |  |  |  |
Beginning balance | 669 | 26 | 11 |  |
Recognized in profit or loss | 2,080 | 643 | 15 |  |
Ending balance | 2,749 | 669 | 26 |  |
Deferred tax asset [member] |  |  |  |  |
Disclosure of the detail of deferred tax assets and liabilities [line items] |  |  |  |  |
Beginning balance | 185,691 | 194,552 | 226,716 |  |
Recognized in profit or loss | (8,092) | (19,259) | (27,981) |  |
Recognized in other comprehensive income | 2,999 | 10,398 | (4,183) |  |
Ending balance | 180,598 | 185,691 | 194,552 |  |
Property, plant and equipment, deferred tax liabilities [member] |  |  |  |  |
Disclosure of the detail of deferred tax assets and liabilities [line items] |  |  |  |  |
Beginning balance | (255,484) | (288,980) | (281,594) |  |
Recognized in profit or loss | 62,797 | 33,496 | (7,386) |  |
Ending balance | (192,687) | (255,484) | (288,980) |  |
Financial assets at fair value through other comprehensive income [member] |  |  |  |  |
Disclosure of the detail of deferred tax assets and liabilities [line items] |  |  |  |  |
Beginning balance | (54,943) | (20,149) | (27,165) |  |
Recognized in other comprehensive income | (30,459) | (34,794) | 7,016 |  |
Ending balance | (85,402) | (54,943) | (20,149) |  |
Deferred tax liabilities [member] |  |  |  |  |
Disclosure of the detail of deferred tax assets and liabilities [line items] |  |  |  |  |
Beginning balance | (310,427) | (309,129) | (308,759) |  |
Recognized in profit or loss | 62,709 | 33,496 | (7,386) |  |
Recognized in other comprehensive income | (30,459) | (34,794) | 7,016 |  |
Ending balance | (278,177) | $ (310,427) | $ (309,129) |  |
Others [member] |  |  |  |  |
Disclosure of the detail of deferred tax assets and liabilities [line items] |  |  |  |  |
Recognized in profit or loss | (88) |  |  |  |
Ending balance | $ (88) |  |  |  |

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