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Financial Assets at Fair Value through Other Comprehensive Income Noncurrent - Additional Information (Detail) - TWD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Disclosure of financial assets [Line Items] |  |  |
Unrealized losses on financial assets at FVOCI |  |  | $ (0.1)
Dividends received | $ 240.0 | $ 167.0 | 157.0
Outstanding Investments [Member] |  |  |
Disclosure of financial assets [Line Items] |  |  |
Dividends received | $ 239.0 | $ 167.0 | 157.0
UUPON Inc. (UUPON) [Member] |  |  |
Disclosure of financial assets [Line Items] |  |  |
Fair value amount |  |  | $ 0.2

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- Definition Noncurrent financial assets at fair value through other comprehensive income. + References No definition available. + Details
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- Definition The amount of dividends received. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 12 -IssueDate 2024-01-01 -Paragraph B12 -Subparagraph a -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=12&code=ifrs-tx-2024-en-r&anchor=para_B12_a&doctype=Appendix&subtype=B -URIDate 2024-03-27 + Details
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- Definition The amount investment funds contribute to the fair value of defined benefit plan assets. [Refer: Plan assets, at fair value; Defined benefit plans [domain]; Investment funds [member]] + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Name IAS -Number 19 -IssueDate 2024-01-01 -Paragraph 142 -Subparagraph f -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2024-en-r&anchor=para_142_f&doctype=Standard -URIDate 2024-03-27 + Details
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- Definition The amount of other comprehensive income, net of tax, related to gains (losses) from changes in the fair value of investments in equity instruments that the entity has designated at fair value through other comprehensive income applying paragraph 5.7.5 of IFRS 9. [Refer: Other comprehensive income] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2024-01-01 -Paragraph 91 -Subparagraph a -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2024-en-r&anchor=para_91_a&doctype=Standard -URIDate 2024-03-27 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2024-01-01 -Paragraph 7 -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2024-en-r&anchor=para_7&doctype=Standard -URIDate 2024-03-27 + Details
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- Details
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