Financial Instruments at Fair Value Through Profit or Loss - Summary of Financial Instruments at Fair Value Through Profit or Loss (Detail) $ in Thousands, $ in Thousands	Dec. 31, 2021 TWD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 TWD ($)
Disclosure of detailed information about financial instruments [line items]
Financial assets mandatorily classified as at FVTPL	$ 5,436,280	$ 195,973	$ 6,523,583
Current	2,933,446	105,748	4,342,605
Non-current	2,502,834	90,225	2,180,978
Financial liabilities held for trading	417,660	15,056	1,537,208
Swap contracts [member] \| Derivative financial instruments [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets mandatorily classified as at FVTPL	85,629	3,087	99,312
Financial liabilities held for trading	360,797	13,006	1,448,972
Forward exchange contracts [member] \| Derivative financial instruments [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets mandatorily classified as at FVTPL	23,373	843	122,511
Financial liabilities held for trading	56,863	2,050	9,020
Redemption option and put option of convertible bonds [member] \| Derivative financial instruments [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets mandatorily classified as at FVTPL	8,463	305
Target redemption forward contracts [member] \| Derivative financial instruments [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets mandatorily classified as at FVTPL	500	18
Financial liabilities held for trading			79,216
Quoted ordinary shares [member] \| Non derivative financial assets [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets mandatorily classified as at FVTPL	2,683,193	96,726	4,064,438
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	1,322,686	47,682	1,124,754
Unquoted preferred shares [member] \| Non derivative financial assets [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets mandatorily classified as at FVTPL	583,270	21,026	385,440
Contingent considerations [member] \| Non derivative financial assets [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets mandatorily classified as at FVTPL	394,943	14,237	387,790
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	$ 334,223	$ 12,049	$ 339,338

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
-Name IFRS
-Number 7
-IssueDate 2021-01-01
-Paragraph 8
-Subparagraph a
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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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Number 7
-IssueDate 2021-01-01
-Paragraph 8
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