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Financial Assets at Fair Value Through Profit or Loss - Summary of Financial Assets at Fair Value Through Profit or Loss (Detail) $ in Thousands, $ in Thousands | Dec. 31, 2020 TWD ($) | Dec. 31, 2020 USD ($) | Dec. 31, 2019 TWD ($)
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Financial Assets At Fair Value Through Profit Or Loss [line items] |  |  |
Current financial assets mandatorily measured at fair value through profit or loss | $ 53,120 | $ 1,892 |
Non-current financial assets mandatorily measured at fair value through profit or loss | 10,368 |  | $ 11,038
Foreign partnership interest [member] |  |  |
Financial Assets At Fair Value Through Profit Or Loss [line items] |  |  |
Non-current financial assets mandatorily measured at fair value through profit or loss | 10,940 |  | 10,940
Listed stocks [member] |  |  |
Financial Assets At Fair Value Through Profit Or Loss [line items] |  |  |
Current financial assets mandatorily measured at fair value through profit or loss | 46,512 |  |
Valuation adjustments [member] |  |  |
Financial Assets At Fair Value Through Profit Or Loss [line items] |  |  |
Current financial assets mandatorily measured at fair value through profit or loss | 6,608 |  |
Non-current financial assets mandatorily measured at fair value through profit or loss | $ (572) |  | $ 98

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- Definition The amount of current financial assets measured at fair value through profit or loss. [Refer: Financial assets at fair value through profit or loss] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2020-01-01 -Paragraph 8 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2020-en-r&anchor=para_8_a&doctype=Standard -URIDate 2020-01-01 + Details
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- Definition The amount of non-current 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] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2020-01-01 -Paragraph 8 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2020-en-r&anchor=para_8_a&doctype=Standard -URIDate 2020-01-01 + Details
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