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Financial Risk Management and Fair Values of Financial Instruments - Summary of Qualitative Information and Sensitivity Analysis of Changes in Significant Unobservable Inputs Under Valuation Model Used in Level Fair Value Measurement (Detail) - TWD ($) | 12 Months Ended
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Dec. 31, 2022 | Dec. 31, 2021
Disclosure of significant unobservable inputs used in fair value measurement of equity [line items] |  |
Fair value | $ 338,102,000 | $ 384,521,000
Non derivative equity instruments [member] | Foreign unlisted stocks [member] |  |
Disclosure of significant unobservable inputs used in fair value measurement of equity [line items] |  |
Fair value | $ 338,102,000 | $ 384,521,000
Valuation technique | Comparable companies | Comparable companies
Non derivative equity instruments [member] | Foreign unlisted stocks [member] | Price book value multiple [member] |  |
Disclosure of significant unobservable inputs used in fair value measurement of equity [line items] |  |
Range (weighted average method) |  | $ 3.46
Relationship of inputs to fair value |  | The higher the multiple, the higher the fair value
Non derivative equity instruments [member] | Foreign unlisted stocks [member] | Enter prise value EBITDA multiple [member] |  |
Disclosure of significant unobservable inputs used in fair value measurement of equity [line items] |  |
Range (weighted average method) | $ 4.82 | $ 9.43
Relationship of inputs to fair value | The higher the multiple, the higher the fair value | The higher the multiple, the higher the fair value
Non derivative equity instruments [member] | Foreign unlisted stocks [member] | Discount for lack of marketability [member] |  |
Disclosure of significant unobservable inputs used in fair value measurement of equity [line items] |  |
Range (weigted average method) | 15.80% | 15.80%
Relationship of inputs to fair value | The higher the discount for lack of marketability, the lower the fair value | The higher the discount for lack of marketability, the lower the fair value

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- Definition The amount of non-current investments in equity instruments that the entity has designated at fair value through other comprehensive income. [Refer: Investments in equity instruments designated at fair value through other comprehensive income] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2022-03-24 -Paragraph 8 -Subparagraph h -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2022-en-r&anchor=para_8_h&doctype=Standard -URIDate 2022-03-24 + Details
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