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Business Combinations - Additional Information (Detail) $ / shares in Units, $ in Thousands, $ in Thousands | 1 Months Ended | 12 Months Ended
--- | --- | ---
Apr. 30, 2018 $ / shares | Dec. 31, 2019 TWD ($) | Dec. 31, 2019 USD ($) | Dec. 31, 2018 TWD ($) | Dec. 31, 2018 USD ($)
Disclosure of subsidiaries [Line Items] |  |  |  |  |
Significant unobservable inputs discount rate |  | 31.00% | 31.00% |  |
Revenue from continuing operations |  | $ 413,782,708 | $ 13,834,260 | $ 397,261,461 |
Profit from continuing operations |  | $ 18,030,506 |  | $ 25,687,447 | $ 602,825
Call option on the remaining non-controlling interests |  | 40.00% | 40.00% |  |
Siliconware Precision Industries Co., Ltd. [member] |  |  |  |  |
Disclosure of subsidiaries [Line Items] |  |  |  |  |
Percentage of shareholdings acquired by subsidiary |  | 100.00% | 100.00% |  |
Cash consideration | $ 51.2 |  |  |  |
UGPL [Member] |  |  |  |  |
Disclosure of subsidiaries [Line Items] |  |  |  |  |
Percentage of shareholdings acquired by subsidiary |  | 60.00% | 60.00% |  |

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- Definition The profit (loss) of the combined entity as though the acquisition date for all business combinations that occurred during the year had been as of the beginning of the annual reporting period. [Refer: Business combinations [member]; Profit (loss)] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 3 -IssueDate 2019-01-01 -Paragraph B64 -Subparagraph q -Clause ii -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=3&code=ifrs-tx-2019-en-r&anchor=para_B64_q_ii&doctype=Appendix&subtype=B -URIDate 2019-03-27 + Details
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- Definition The revenue of the combined entity as though the acquisition date for all business combinations that occurred during the year had been as of the beginning of the annual reporting period. [Refer: Business combinations [member]; Revenue] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 3 -IssueDate 2019-01-01 -Paragraph B64 -Subparagraph q -Clause ii -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=3&code=ifrs-tx-2019-en-r&anchor=para_B64_q_ii&doctype=Appendix&subtype=B -URIDate 2019-03-27 + Details
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