Financial Instruments at Fair Value Through Profit or Loss (FVTPL) - Summary of Financial Instruments at Fair Value Through Profit or Loss (Detail) $ in Thousands, $ in Thousands	Dec. 31, 2024 TWD ($)	Dec. 31, 2024 USD ($)	Dec. 31, 2023 TWD ($)
Disclosure of detailed information about financial instruments [line items]
Financial assets mandatorily classified as at FVTPL	$ 10,832,042	$ 330,346	$ 6,628,690
Current	8,390,606	255,889	4,084,715
Non-current	2,441,436	74,457	2,543,975
Total	10,832,042	330,346	6,628,690
Financial liabilities held for trading	832,869	25,399	1,302,342
Current	324,278	9,889	1,302,342
Non-current	508,591	15,510	0
Total	832,869	25,399	1,302,342
Derivative financial instruments [member]
Disclosure of detailed information about financial instruments [line items]
Financial liabilities held for trading	243,752	7,433	1,302,342
Swap contracts [member] \| Derivative financial instruments [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets mandatorily classified as at FVTPL	4,282,512	130,604	1,453,868
Financial liabilities held for trading	179,967	5,488	1,183,469
Forward exchange contracts [member] \| Derivative financial instruments [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets mandatorily classified as at FVTPL	258,362	7,879	161,924
Financial liabilities held for trading	63,785	1,945	118,873
Contingent considerations [member] \| Derivative financial instruments [member]
Disclosure of detailed information about financial instruments [line items]
Financial liabilities held for trading	589,117	17,966
Contingent considerations [member] \| Non-derivative financial assets [member]
Disclosure of detailed information about financial instruments [line items]
Financial liabilities held for trading	589,117	17,966	0
Quoted shares [member] \| Non-derivative financial assets [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets mandatorily classified as at FVTPL	2,898,751	88,404	2,099,844
Private-placement funds [member] \| Non-derivative financial assets [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets mandatorily classified as at FVTPL	1,503,382	45,849	1,796,015
Unquoted shares [member] \| Non-derivative financial assets [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets mandatorily classified as at FVTPL	863,484	26,334	747,960
Open-end mutual funds [member] \| Non-derivative financial assets [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets mandatorily classified as at FVTPL	590,346	18,004	307,669
Convertible Notes [Member] \| Hybrid financial assets [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets mandatorily classified as at FVTPL	360,635	10,998	61,410
Preferred shares with warrants [Member] \| Hybrid financial assets [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets mandatorily classified as at FVTPL	65,570	2,000	0
Documentary investment agreement [member] \| Hybrid financial assets [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets mandatorily classified as at FVTPL	$ 9,000	$ 274	$ 0

The amount of current financial assets measured at fair value through profit or loss. [Refer: Financial assets at fair value through profit or loss]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Number 7
-IssueDate 2024-01-01
-Paragraph 8
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The amount of current financial assets mandatorily measured at fair value through profit or loss in accordance with IFRS 9. [Refer: Financial assets at fair value through profit or loss, mandatorily measured at fair value]

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The amount of current financial liabilities measured at fair value through profit or loss. [Refer: Financial liabilities at fair value through profit or loss]

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2024-01-01
-Paragraph 8
-Subparagraph e
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2024-en-r&anchor=para_8_e&doctype=Standard
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The amount of current financial liabilities at fair value through profit or loss that meet the definition of held for trading. [Refer: Current financial liabilities at fair value through profit or loss]

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The amount of financial assets that are measured at fair value and for which gains (losses) are recognised in profit or loss. A financial asset shall be measured at fair value through profit or loss unless it is measured at amortised cost or at fair value through other comprehensive income. A gain (loss) on a financial asset measured at fair value shall be recognised in profit or loss unless it is part of a hedging relationship, it is an investment in an equity instrument for which the entity has elected to present gains and losses in other comprehensive income or it is a financial asset measured at fair value through other comprehensive income. [Refer: At fair value [member]; Financial assets]

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The amount of financial liabilities that meet either of the following conditions: (a) they meet the definition of held for trading; or (b) upon initial recognition they are designated by the entity as at fair value through profit or loss. An entity may use this designation only when permitted by paragraph 4.3.5 of IFRS 9 (embedded derivatives) or when doing so results in more relevant information, because either: (a) it eliminates or significantly reduces a measurement or recognition inconsistency (sometimes referred to as ‘an accounting mismatch’) that would otherwise arise from measuring assets or liabilities or recognising the gains and losses on them on different bases; or (b) a group of financial liabilities or financial assets and financial liabilities is managed and its performance is evaluated on a fair value basis, in accordance with a documented risk management or investment strategy, and information about the group is provided internally on that basis to the entity’s key management personnel (as defined in IAS 24). [Refer: At fair value [member]; Key management personnel of entity or parent [member]; Derivatives [member]; Financial assets; Financial liabilities]

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The amount of non-current financial assets measured at fair value through profit or loss. [Refer: Financial assets at fair value through profit or loss]

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The amount of non-current financial liabilities measured at fair value through profit or loss. [Refer: Financial liabilities at fair value through profit or loss]

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