The amount of 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 current financial assets measured at fair value through profit or loss classified as held for trading. [Refer: Financial assets at fair value through profit or loss, classified as held for trading]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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The amount of current financial assets measured at fair value through profit or loss that were designated as such upon initial recognition or subsequently. [Refer: Financial assets at fair value through profit or loss, designated upon initial recognition or subsequently]

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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 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]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table.

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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 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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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, 2018 USD ($)	Dec. 31, 2018 TWD ($)	Dec. 31, 2017 TWD ($)
Disclosure of detailed information about financial instruments [line items]
Financial assets designated as at FVTPL			$ 100,496
Financial assets held for trading			5,122,571
Financial assets mandatorily classified as at FVTPL	$ 258,035	$ 7,898,458
Financial assets at fair value through profit or loss	258,035	7,898,458	5,223,067
Current	237,250	7,262,227	5,223,067
Non-current	20,785	636,231
Financial liabilities held for trading	1,197	36,655	677,430
Private-placement convertible bonds [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets designated as at FVTPL			100,496
Private-placement convertible bonds [member] \| Hybrid financial assets [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets mandatorily classified as at FVTPL	3,283	100,496
Quoted ordinary shares [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets held for trading			4,410,732
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	168,287	5,151,255
Open-end mutual funds [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets held for trading			589,976
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	19,007	581,800
Forward Exchange Contract [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets held for trading			61,325
Forward Exchange Contract [member] \| Derivative financial instruments [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets mandatorily classified as at FVTPL	1,048	32,070
Swap contracts [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets held for trading			60,538
Swap contracts [member] \| Derivative financial instruments [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets mandatorily classified as at FVTPL	50,889	1,557,714
Financial liabilities held for trading	949	29,058	652,107
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	8,984	275,000
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	6,537	200,123
Forward exchange contracts [member] \| Derivative financial instruments [member]
Disclosure of detailed information about financial instruments [line items]
Financial liabilities held for trading	$ 248	$ 7,597	$ 25,323