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Hedging Derivative Financial Instruments - Summary of Hedging Transaction and Reclassification Affected Comprehensive Income (Details) - Forecast Purchases - forward Exchange Contract [Member] - Cash flow hedges [member] $ in Millions | 12 Months Ended
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Dec. 31, 2018 TWD ($)
Disclosure Of Reclassification Of Financial Assets [Line Items] |
Hedging Gain or Loss Recognized in OCI | $ 2
Amount Reclassified to P/L and the Adjusted Line Item | $ (4)

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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. + Details
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- Definition The gain (loss) recognised in other comprehensive income on hedge ineffectiveness. [Refer: Gain (loss) on hedge ineffectiveness] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2018-01-01 -Paragraph 24C -Subparagraph a -Clause i -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2018-03-01&anchor=para_24C_a_i&doctype=Standard -URIDate 2018-03-16 + Details
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- Definition The amount of financial assets reclassified out of the at fair value through profit or loss category. [Refer: Financial assets at fair value through profit or loss] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Note Expiry date 2021-01-01 -Name IFRS -Number 7 -IssueDate 2018-01-01 -Paragraph 12A -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2017-03-02&anchor=para_12A_a&doctype=Standard&book=b -URIDate 2018-03-16 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Note Expiry date 2021-01-01 -Name IFRS -Number 7 -IssueDate 2018-01-01 -Paragraph 12 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2017-03-02&anchor=para_12&doctype=Standard&book=b -URIDate 2018-03-16 + Details
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