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v3.19.1

Long Term Loans - Summary of Long-term Loans (Detail) - Long-term loans [Member] - TWD ($) $ in Millions | Dec. 31, 2018 | Dec. 31, 2017
--- | --- | ---
Disclosure of detailed information about borrowings [Line Items] |  |
Secured loans | $ 1,600 | $ 1,600
Secured loans [Member] |  |
Disclosure of detailed information about borrowings [Line Items] |  |
Interest rates of loans | 0.92% | 0.91%

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- Definition The interest rate on borrowings. [Refer: Borrowings] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IFRS -Number 7 -IssueDate 2018-01-01 -Paragraph 7 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2018-03-01&anchor=para_7&doctype=Standard -URIDate 2018-03-16 + Details
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Period Type: | instant

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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 amount of loans received from banks that have been secured by collateral. [Refer: Loans received] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2018-01-01 -Paragraph 112 -Subparagraph c -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_112_c&doctype=Standard -URIDate 2018-03-16 + Details
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Period Type: | instant

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- Details
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Namespace Prefix: |
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- Details
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Balance Type: |
Period Type: |