Hedging Financial Instruments - Summary of Hedging Derivative Financial Instruments (Detail) - Cash flow hedges [member] - Forward exchange contracts [Member] $ in Millions	Dec. 31, 2017 TWD ($)
Disclosure Of Detailed Information About Hedging Instruments [Line Items]
Cash flow hedge - forward exchange contracts, financial assets	$ 0
Cash flow hedge-forward exchange contracts, financial liabilities	$ 1

The amount of financial assets classified as derivative instruments. [Refer: Financial assets; Derivatives [member]]

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2019-01-01
-Paragraph 55
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-URIDate 2019-03-27

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- Definition

The amount of financial liabilities classified as derivative instruments. [Refer: Financial assets; Derivatives [member]]

+ References

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- Definition

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.

+ References

No definition available.

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