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Financial Risk Management and Fair Values of Financial Instruments - Summary of Movements of Level 3 (Detail) $ in Thousands, $ in Thousands | 12 Months Ended
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Dec. 31, 2024 TWD ($) | Dec. 31, 2024 USD ($) | Dec. 31, 2023 TWD ($) | Dec. 31, 2022 TWD ($)
Disclosure of detailed information about financial instruments [Line Items] |  |  |  |
Gains or losses recognized in profit or loss Recorded as non-operating income (expenses) | $ (48,101) | $ (1,467) | $ (39,254) | $ 69,404
Gains or losses recognized in other comprehensive gains (losses) Recorded as unrealized gain (loss) on valuation of financial assets at fair value through other comprehensive income | (17,304) | $ (528) | (217,785) | (46,419)
Level 3 [member] | Equity instruments [member] |  |  |  |
Disclosure of detailed information about financial instruments [Line Items] |  |  |  |
Movement of financial instruments beginning balance | 120,317 |  | 338,102 |
Gains or losses recognized in other comprehensive gains (losses) Recorded as unrealized gain (loss) on valuation of financial assets at fair value through other comprehensive income | (17,304) |  | (217,785) |
Purchases |  |  | 12,500 |
Reclassified as investments accounted for using equity method |  |  | (12,500) |
Movement of financial instruments ending balance | $ 103,013 |  | $ 120,317 | $ 338,102

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- Definition The cash inflow from sales or maturity of financial instruments, classified as investing activities. [Refer: Classes of financial instruments [domain]] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 7 -IssueDate 2024-01-01 -Paragraph 16 -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=7&code=ifrs-tx-2024-en-r&anchor=para_16&doctype=Standard -URIDate 2024-03-27 + Details
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