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Profit Before Income Tax - Additional Information (Detail) $ in Thousands | 1 Months Ended | 12 Months Ended
--- | --- | ---
Apr. 30, 2019 TWD ($) | Apr. 30, 2019 USD ($) | Dec. 31, 2019 TWD ($) | Dec. 31, 2019 USD ($) | Dec. 31, 2018 TWD ($)
Analysis of income and expense [Line Items] |  |  |  |  |
Percentage of employees' compensation |  |  | 0.20% | 0.20% | 0.20%
Percentage of remuneration to directors |  |  | 0.40% | 0.40% | 0.15%
Gain recognized from remeasuring fair value of equity interest before business combination | $ 243,057 | $ 8,126,000 |  |  |
Difference Between Employee Compensation Benefits And Director Remuneration Adjusted In Net Profit |  |  | $ 3 | $ 100 |
Siliconware Precision Industries Co., Ltd. [member] |  |  |  |  |
Analysis of income and expense [Line Items] |  |  |  |  |
Gain recognized from remeasuring fair value of equity interest before business combination |  |  |  |  | $ 7,421,408
Bottom of range [member] |  |  |  |  |
Analysis of income and expense [Line Items] |  |  |  |  |
Percentage of employees' compensation |  |  | 0.01% | 0.01% |
Top of range [member] |  |  |  |  |
Analysis of income and expense [Line Items] |  |  |  |  |
Percentage of employees' compensation |  |  | 1.00% | 1.00% |
Percentage of remuneration to directors |  |  | 0.75% | 0.75% |

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- Definition The gain (loss) recognised as result of remeasuring to fair value the equity interest in the acquiree held by the acquirer before the 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 p -Clause ii -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=3&code=ifrs-tx-2019-en-r&anchor=para_B64_p_ii&doctype=Appendix&subtype=B -URIDate 2019-03-27 + Details
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