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Revenue - Summary of Contract Assets and Liabilities (Detail) - TWD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019 | Jan. 01, 2019
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Disclosure of contract assets and liabilities in relation to revenue [Abstract] |  |  |
Contract assets | $ 389,016 | $ 377,869 | $ 299,835
Contract liabilities (Advance payments) |  | $ 1,231 | $ 1,432

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- Definition The amount of an entity’s right to consideration in exchange for goods or services that the entity has transferred to a customer, when that right is conditioned on something other than the passage of time (for example, the entity’s future performance). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 15 -IssueDate 2020-01-01 -Paragraph 105 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=15&code=ifrs-tx-2020-en-r&anchor=para_105&doctype=Standard -URIDate 2020-01-01 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 15 -IssueDate 2020-01-01 -Paragraph 116 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=15&code=ifrs-tx-2020-en-r&anchor=para_116_a&doctype=Standard -URIDate 2020-01-01 + Details
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- Definition The amount of an entity’s obligation to transfer goods or services to a customer for which the entity has received consideration (or the amount is due) from the customer. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 15 -IssueDate 2020-01-01 -Paragraph 105 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=15&code=ifrs-tx-2020-en-r&anchor=para_105&doctype=Standard -URIDate 2020-01-01 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 15 -IssueDate 2020-01-01 -Paragraph 116 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=15&code=ifrs-tx-2020-en-r&anchor=para_116_a&doctype=Standard -URIDate 2020-01-01 + Details
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Period Type: | instant

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- Definition Disclosure of contract assets and liabilities in relation to revenue. + References No definition available. + Details
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