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v3.19.1

Property, Plant and Equipment - Additional Information (Detail) $ in Millions, $ in Millions | 12 Months Ended
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Dec. 31, 2018 TWD ($) | Dec. 31, 2018 USD ($) | Dec. 31, 2017 TWD ($) | Dec. 31, 2016 TWD ($)
Disclosure of detailed information about property, plant and equipment [Line Items] |  |  |  |
Impairment losses | $ 0.0 | $ 0 | $ 0.0 | $ 596.0
Telecommunications equipment [Member] |  |  |  |
Disclosure of detailed information about property, plant and equipment [Line Items] |  |  |  |
Impairment losses |  |  |  | 596.0
Partial computer and miscellaneous equipment [Member] |  |  |  |
Disclosure of detailed information about property, plant and equipment [Line Items] |  |  |  |
Impairment losses |  |  |  | $ 0.4

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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 amount of impairment loss recognised in profit or loss for property, plant and equipment. [Refer: Impairment loss recognised in profit or loss; Property, plant and equipment] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 16 -IssueDate 2018-01-01 -Paragraph 73 -Subparagraph e -Clause v -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=16&date=2018-03-01&anchor=para_73_e_v&doctype=Standard -URIDate 2018-03-16 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2018-01-01 -Paragraph 98 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_98_a&doctype=Standard -URIDate 2018-03-16 + Details
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- Details
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