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v3.23.1

Income Tax Expense - Reconciliation of Income Tax Expense and Accounting Profit Before Income Tax (Detail) $ in Thousands, $ in Thousands | 12 Months Ended
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Dec. 31, 2022 TWD ($) | Dec. 31, 2022 USD ($) | Dec. 31, 2021 TWD ($) | Dec. 31, 2020 TWD ($)
Reconciliation of income tax expense and accounting profit before income tax [abstract] |  |  |  |
Tax calculated based on profit before tax and statutory tax rate | $ 804,086 |  | $ 1,207,605 | $ 595,258
Effects from adjustments based on regulation | (131,873) |  | (152,618) | 26,974
Gain on investment in associates | 11,923 |  |  |
Temporary difference not recognized as deferred tax assets |  |  |  | (4)
Prior year income tax overestimation | (255,935) |  | (184,284) | (133,923)
Income tax on unappropriated retained earnings | 159,744 |  | 227,467 | 105,665
Effect of different tax rates in countries in which the Group operates | 230 |  | 148 | 411
Income tax expense | $ 588,175 | $ 19,140 | $ 1,098,318 | $ 594,381

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- Definition The aggregate amount included in the determination of profit (loss) for the period in respect of current tax and deferred tax. [Refer: Current tax expense (income); Deferred tax expense (income)] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 26 -IssueDate 2022-03-24 -Paragraph 35 -Subparagraph b -Clause viii -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=26&code=ifrs-tx-2022-en-r&anchor=para_35_b_viii&doctype=Standard -URIDate 2022-03-24 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 8 -IssueDate 2022-03-24 -Paragraph 23 -Subparagraph h -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=8&code=ifrs-tx-2022-en-r&anchor=para_23_h&doctype=Standard -URIDate 2022-03-24 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 12 -IssueDate 2022-03-24 -Paragraph 79 -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=12&code=ifrs-tx-2022-en-r&anchor=para_79&doctype=Standard -URIDate 2022-03-24 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 12 -IssueDate 2022-03-24 -Paragraph 81 -Subparagraph c -Clause i -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=12&code=ifrs-tx-2022-en-r&anchor=para_81_c_i&doctype=Standard -URIDate 2022-03-24 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 12 -IssueDate 2022-03-24 -Paragraph 81 -Subparagraph c -Clause ii -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=12&code=ifrs-tx-2022-en-r&anchor=para_81_c_ii&doctype=Standard -URIDate 2022-03-24 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 12 -IssueDate 2022-03-24 -Paragraph B13 -Subparagraph g -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=12&code=ifrs-tx-2022-en-r&anchor=para_B13_g&doctype=Appendix&subtype=B -URIDate 2022-03-24 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2022-03-24 -Paragraph 82 -Subparagraph d -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2022-en-r&anchor=para_82_d&doctype=Standard -URIDate 2022-03-24 + Details
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- Definition The amount that represents the difference between the tax expense (income) and the product of the accounting profit multiplied by the applicable tax rate(s) that relates to foreign tax rates. [Refer: Accounting profit] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 12 -IssueDate 2022-03-24 -Paragraph 81 -Subparagraph c -Clause i -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=12&code=ifrs-tx-2022-en-r&anchor=para_81_c_i&doctype=Standard -URIDate 2022-03-24 + Details
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- Definition Reconciliation of income tax expense and accounting profit before income tax. + References No definition available. + Details
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