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Business Combinations - Summary of Subsidiary Acquired (Detail) $ in Thousands, $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2019 TWD ($) | Dec. 31, 2019 USD ($)
SPIL [member] |  |
Disclosure of detailed information about business combination [Line Items] |  |
Principal Activity | Engaged in the assembly, testing and turnkey services of integrated circuits |
Date of Acquisition | Apr. 30, 2018 |
Proportion of Voting Equity Interests Acquired | 100.00% | 100.00%
Cash Consideration | $ 168,440,585 |
AMPI [member] |  |
Disclosure of detailed information about business combination [Line Items] |  |
Principal Activity | Engaged in the manufacturing of integrated circuit |
Date of Acquisition | Apr. 30, 2019 |
Proportion of Voting Equity Interests Acquired | 50.97% | 50.97%
Cash Consideration | $ 250,000 | $ 8,358
ASEEE [member] |  |
Disclosure of detailed information about business combination [Line Items] |  |
Principal Activity | Engaged in the production of embedded substrate |
Date of Acquisition | Apr. 26, 2019 |
Proportion of Voting Equity Interests Acquired | 51.00% | 51.00%
Cash Consideration | $ 0 | $ 0
UGPL [Member] |  |
Disclosure of detailed information about business combination [Line Items] |  |
Principal Activity | Engaged in designing, miniaturization, material sourcing, manufacturing, logistics, and after services of electronic devices and modules |
Date of Acquisition | Oct. 31, 2019 |
Proportion of Voting Equity Interests Acquired | 60.00% | 60.00%
Cash Consideration | $ 313,057 | $ 10,467

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- Definition The fair value, at acquisition date, of the consideration transferred in a business combination. [Refer: Business combinations [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 3 -IssueDate 2019-01-01 -Paragraph B64 -Subparagraph f -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=3&code=ifrs-tx-2019-en-r&anchor=para_B64_f&doctype=Appendix&subtype=B -URIDate 2019-03-27 + Details
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- Definition The date on which the acquirer obtains control of the acquiree in a business combination. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 3 -IssueDate 2019-01-01 -Paragraph B64 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=3&code=ifrs-tx-2019-en-r&anchor=para_B64_b&doctype=Appendix&subtype=B -URIDate 2019-03-27 + Details
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- Definition The description of the nature of the entity's operations and principal activities. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2019-01-01 -Paragraph 138 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2019-en-r&anchor=para_138_b&doctype=Standard -URIDate 2019-03-27 + Details
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- Definition The percentage of voting equity interests acquired in a business combination. [Refer: Business combinations [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 3 -IssueDate 2019-01-01 -Paragraph B64 -Subparagraph c -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=3&code=ifrs-tx-2019-en-r&anchor=para_B64_c&doctype=Appendix&subtype=B -URIDate 2019-03-27 + Details
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