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Financial Assets at Fair Value Through Profit or Loss - Summary of Amounts recognized in Profit or Loss in Relation to Financial Assets at Fair Value Through Profit or Loss (Detail) $ in Thousands, $ in Thousands | 12 Months Ended
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Dec. 31, 2020 TWD ($) | Dec. 31, 2020 USD ($) | Dec. 31, 2019 TWD ($) | Dec. 31, 2018 TWD ($)
Financial Assets At Fair Value Through Profit Or Loss [line items] |  |  |  |
Financial assets mandatorily measured at fair value through profit or loss | $ 24,015 | $ 855 | $ 1,317 | $ 1,485
Foreign partnership interest [member] |  |  |  |
Financial Assets At Fair Value Through Profit Or Loss [line items] |  |  |  |
Financial assets mandatorily measured at fair value through profit or loss | (670) |  | (433) | 38
Beneficiary certificates [member] |  |  |  |
Financial Assets At Fair Value Through Profit Or Loss [line items] |  |  |  |
Financial assets mandatorily measured at fair value through profit or loss | 18,077 |  | $ 1,750 | 1,396
Derivative instrument [member] |  |  |  |
Financial Assets At Fair Value Through Profit Or Loss [line items] |  |  |  |
Financial assets mandatorily measured at fair value through profit or loss |  |  |  | $ 51
Listed stocks [member] |  |  |  |
Financial Assets At Fair Value Through Profit Or Loss [line items] |  |  |  |
Financial assets mandatorily measured at fair value through profit or loss | $ 6,608 |  |  |

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- Definition The gains (losses) on financial assets mandatorily measured at fair value through profit or loss in accordance with IFRS 9. [Refer: Financial assets at fair value through profit or loss, mandatorily measured at fair value; Gains (losses) on financial assets at fair value through profit or loss; Financial liabilities] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2020-01-01 -Paragraph 20 -Subparagraph a -Clause i -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2020-en-r&anchor=para_20_a_i&doctype=Standard -URIDate 2020-01-01 + Details
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- Definition Financial assets at fair value through profit or loss. + References No definition available. + Details
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