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v3.19.1

Operating Lease Arrangements - Additional Information (Detail) $ in Thousands, $ in Thousands | 12 Months Ended
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Dec. 31, 2018 USD ($) | Dec. 31, 2018 TWD ($) | Dec. 31, 2017 TWD ($) | Dec. 31, 2016 TWD ($)
Disclosure of operating lease [line items] |  |  |  |
Operating lease expiration | 2019 to 2028 | 2019 to 2028 |  |
Rental expense | $ 52,052 | $ 1,593,315 | $ 1,193,477 | $ 1,411,533
Bottom of range [member] |  |  |  |
Disclosure of operating lease [line items] |  |  |  |
Operating leasing periods | 1 year | 1 year |  |
Top of range [member] |  |  |  |
Disclosure of operating lease [line items] |  |  |  |
Operating leasing periods | 15 years | 15 years |  |

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- Definition Description of operating lease expiration. + References No definition available. + Details
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Period Type: | duration

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- Definition Disclosure of operating lease [line items]. + References No definition available. + Details
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- Definition Operating lease Term + References No definition available. + Details
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- Definition The amount of payments on leases and subleases recognised as an expense by the lessee. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Note Expiry date 2019-01-01 -Name IAS -Number 17 -IssueDate 2018-01-01 -Paragraph 35 -Subparagraph c -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=17&date=2018-03-02&anchor=para_35_c&doctype=Standard&book=b -URIDate 2018-03-16 + Details
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- Details
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- Details
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