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Share-based Payments - Additional Information (Detail) $ in Thousands | 12 Months Ended
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Dec. 31, 2019 TWD ($) | Dec. 31, 2018 TWD ($)
Disclosure of terms and conditions of share-based payment arrangement [Line Items] |  |
Compensation expenses | $ 822 | $ 41,043
Restricted shares award agreement [member] |  |
Disclosure of terms and conditions of share-based payment arrangement [Line Items] |  |
Restricted shares outstanding shares | 0 |

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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 expense from share-based payment transactions with employees. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2020-01-01 -Paragraph 112 -Subparagraph c -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2020-en-r&anchor=para_112_c&doctype=Standard -URIDate 2020-01-01 + Details
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Balance Type: | debit
Period Type: | duration

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- Definition The number of other equity instruments (ie other than share options) outstanding in a share-based payment arrangement. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IFRS -Number 2 -IssueDate 2020-01-01 -Paragraph 45 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2020-en-r&anchor=para_45&doctype=Standard -URIDate 2020-01-01 + Details
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- Details
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Balance Type: |
Period Type: |