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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, 2024 | Dec. 31, 2023
Disclosure of significant unobservable inputs used in fair value measurement of equity [line items] |  |
Fair value | $ 103,013,000 | $ 120,317,000
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 | $ 103,013,000 | $ 120,317,000
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 |  | $ 1.64
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] | Price book value multiple [member] | Bottom of range [member] |  |
Disclosure of significant unobservable inputs used in fair value measurement of equity [line items] |  |
Range | $ 1.36 |
Non derivative equity instruments [member] | Foreign unlisted stocks [member] | Price book value multiple [member] | Top of range [member] |  |
Disclosure of significant unobservable inputs used in fair value measurement of equity [line items] |  |
Range | 1.53 |
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 | $ 8.9 | $ 8.23
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) | 15.60% | 15.70%
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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