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Income Tax - Summary of Unrecognized Deferred Tax Assets Related to Loss Carry-forward, Investment Credits and Deductible Temporary Differences (Detail) $ in Thousands, $ in Thousands | Dec. 31, 2019 TWD ($) | Dec. 31, 2019 USD ($) | Dec. 31, 2018 TWD ($)
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Disclosure of temporary difference, unused tax losses and unused tax credits [abstract] |  |  |
Loss carry-forward | $ 966,783 | $ 32,323 | $ 666,043
Investment credits | 51,217 | 1,712 |
Deductible temporary differences | 446,754 | 14,937 | 332,255
Unrecognized deferred tax assets | $ 1,464,754 | $ 48,792 | $ 998,298

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- Definition Unrecognized deferred tax assets. + References No definition available. + Details
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- Definition The amount of deductible temporary differences for which no deferred tax asset is recognised in the statement of financial position. [Refer: Temporary differences [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 12 -IssueDate 2019-01-01 -Paragraph 81 -Subparagraph e -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=12&code=ifrs-tx-2019-en-r&anchor=para_81_e&doctype=Standard -URIDate 2019-03-27 + Details
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- Definition The amount of unused tax credits for which no deferred tax asset is recognised in the statement of financial position. [Refer: Unused tax credits [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 12 -IssueDate 2019-01-01 -Paragraph 81 -Subparagraph e -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=12&code=ifrs-tx-2019-en-r&anchor=para_81_e&doctype=Standard -URIDate 2019-03-27 + Details
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- Definition The amount of unused tax losses for which no deferred tax asset is recognised in the statement of financial position. [Refer: Unused tax losses [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 12 -IssueDate 2019-01-01 -Paragraph 81 -Subparagraph e -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=12&code=ifrs-tx-2019-en-r&anchor=para_81_e&doctype=Standard -URIDate 2019-03-27 + Details
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