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v3.20.1

Investment in Associates - Additional Information (Detail) $ in Thousands, $ in Thousands |  | 1 Months Ended | 12 Months Ended
--- | --- | --- | ---
Apr. 08, 2019 TWD ($) shares | Jan. 31, 2018 TWD ($) | Dec. 31, 2019 TWD ($) | Dec. 31, 2019 USD ($) | Dec. 31, 2018 TWD ($) | Dec. 31, 2017 TWD ($)
Disclosure of associates [line items] |  |  |  |  |  |
Acquisition of investment in associate |  |  |  |  | $ 794,694 | $ 1,373,486
Share of profit (loss) of investment associates |  |  | $ 154,926 |  | (300,101) |
Cash consideration from disposals of investment in associates |  |  | 1,180,179 | $ 39,458 |  |
Gain on disposal of investment in associates |  |  | 973,609 | $ 32,551 |  | $ 16,929
JMC ELECTRONICS CO., LTD. [member] |  |  |  |  |  |
Disclosure of associates [line items] |  |  |  |  |  |
Investment in associates at fair value |  |  | $ 807,000 |  | $ 2,081,900 |
Number of common shares disposed | shares | 9,100,000 |  |  |  |  |
Percentage of ownership interest in associate | 10.00% |  | 10.00% | 10.00% | 19.10% |
Cash consideration from disposals of investment in associates | $ 1,180,179 |  |  |  |  |
Gain on disposal of investment in associates | $ 973,609 |  |  |  |  |
Unimos Shanghai [member] |  |  |  |  |  |
Disclosure of associates [line items] |  |  |  |  |  |
Acquisition of investment in associate |  | $ 794,694 |  |  |  |
Percentage of ownership interest in associate |  |  | 45.02% | 45.02% | 45.02% |

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- Definition The cash inflow from sales of investments accounted for using the equity method. [Refer: Investments accounted for using equity method] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 7 -IssueDate 2019-01-01 -Paragraph 16 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=7&code=ifrs-tx-2019-en-r&anchor=para_16&doctype=Standard -URIDate 2019-03-27 + Details
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- Definition The proportion of ownership interest in an associate attributable to the entity. [Refer: Associates [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 27 -IssueDate 2019-01-01 -Paragraph 17 -Subparagraph b -Clause iii -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=27&code=ifrs-tx-2019-en-r&anchor=para_17_b_iii&doctype=Standard -URIDate 2019-03-27 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 27 -IssueDate 2019-01-01 -Paragraph 16 -Subparagraph b -Clause iii -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=27&code=ifrs-tx-2019-en-r&anchor=para_16_b_iii&doctype=Standard -URIDate 2019-03-27 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 12 -IssueDate 2019-01-01 -Paragraph 21 -Subparagraph a -Clause iv -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=12&code=ifrs-tx-2019-en-r&anchor=para_21_a_iv&doctype=Standard -URIDate 2019-03-27 + Details
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