The amount of current financial assets at fair value through other comprehensive income. [Refer: Financial assets at fair value through other comprehensive income]

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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]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
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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 assets measured at fair value through other comprehensive income. [Refer: Financial assets measured at fair value through other comprehensive income]

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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
-Name IFRS
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The amount of current investments in equity instruments that the entity has designated at fair value through other comprehensive income. [Refer: Investments in equity instruments designated at fair value through other comprehensive income]

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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-derivative financial assets that are designated as available for sale or are not classified as (a) loans and receivables; (b) held-to-maturity investments; or (c) financial assets at fair value through profit or loss. [Refer: Derivative financial assets; Financial assets at fair value through profit or loss; Held-to-maturity investments]

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Financial Instruments - Summary of Fair Value of Financial Instruments that are Measured at Fair Value on a Recurring Basis (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 at fair value through profit or loss	$ 258,035	$ 7,898,458	5,223,067
Available-for-sale financial assets			1,212,165
Financial assets mandatorily classified as at FVTPL	258,035	7,898,458
Financial assets at FVTOCI	52,183	1,597,323
Financial liabilities at FVTPL	1,197	36,655	677,430
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 at FVTPL	949	29,058	652,107
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
Quoted ordinary shares [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets held for trading			4,410,732
Available-for-sale financial assets			279,791
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
Available-for-sale financial assets			23,825
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
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
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
Unquoted ordinary shares [member]
Disclosure of detailed information about financial instruments [line items]
Available-for-sale financial assets			662,477
Financial assets at FVTOCI, Investments in equity instruments	17,665	540,730
Limited partnership [member]
Disclosure of detailed information about financial instruments [line items]
Available-for-sale financial assets			246,072
Financial assets at FVTOCI, Investments in equity instruments	1,296	39,669
Unsecured subordinate corporate bonds [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets at FVTOCI, Investments in debt instruments	33,222	1,016,924
Forward exchange contracts [member] \| Derivative financial instruments [member]
Disclosure of detailed information about financial instruments [line items]
Financial liabilities at FVTPL	248	7,597	25,323
Level 1 of fair value hierarchy [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets at fair value through profit or loss			5,000,708
Available-for-sale financial assets			303,616
Financial assets mandatorily classified as at FVTPL	187,294	5,733,055
Level 1 of fair value hierarchy [member] \| Quoted ordinary shares [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets held for trading			4,410,732
Available-for-sale financial assets			279,791
Level 1 of fair value hierarchy [member] \| 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
Level 1 of fair value hierarchy [member] \| Open-end mutual funds [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets held for trading			589,976
Available-for-sale financial assets			23,825
Level 1 of fair value hierarchy [member] \| 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
Level 2 of fair value hierarchy [Member]
Disclosure of detailed information about financial instruments [line items]
Financial assets at fair value through profit or loss			222,359
Financial assets mandatorily classified as at FVTPL	55,220	1,690,280
Financial liabilities at FVTPL	1,197	36,655	677,430
Level 2 of fair value hierarchy [Member] \| Swap contracts [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets held for trading			60,538
Level 2 of fair value hierarchy [Member] \| 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 at FVTPL	949	29,058	652,107
Level 2 of fair value hierarchy [Member] \| Forward Exchange Contract [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets held for trading			61,325
Level 2 of fair value hierarchy [Member] \| 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
Level 2 of fair value hierarchy [Member] \| Private-placement convertible bonds [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets designated as at FVTPL			100,496
Level 2 of fair value hierarchy [Member] \| 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
Level 2 of fair value hierarchy [Member] \| Forward exchange contracts [member] \| Derivative financial instruments [member]
Disclosure of detailed information about financial instruments [line items]
Financial liabilities at FVTPL	248	7,597	25,323
Level 3 of fair value hierarchy [member]
Disclosure of detailed information about financial instruments [line items]
Available-for-sale financial assets			908,549
Financial assets mandatorily classified as at FVTPL	15,521	475,123
Financial assets at FVTOCI	52,183	1,597,323
Level 3 of fair value hierarchy [member] \| 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
Level 3 of fair value hierarchy [member] \| 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
Level 3 of fair value hierarchy [member] \| Unquoted ordinary shares [member]
Disclosure of detailed information about financial instruments [line items]
Available-for-sale financial assets			662,477
Financial assets at FVTOCI, Investments in equity instruments	17,665	540,730
Level 3 of fair value hierarchy [member] \| Limited partnership [member]
Disclosure of detailed information about financial instruments [line items]
Available-for-sale financial assets			$ 246,072
Financial assets at FVTOCI, Investments in equity instruments	1,296	39,669
Level 3 of fair value hierarchy [member] \| Unsecured subordinate corporate bonds [member]
Disclosure of detailed information about financial instruments [line items]
Financial assets at FVTOCI, Investments in debt instruments	$ 33,222	$ 1,016,924