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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, 2023 | Dec. 31, 2022
Disclosure of significant unobservable inputs used in fair value measurement of equity [line items] |  |
Fair value | $ 120,317,000 | $ 338,102,000
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 | $ 120,317,000 | $ 338,102,000
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) | $ 1.64 |
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) | $ 8.23 | $ 4.82
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) | 15.70% | 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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