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v3.20.1

Others - Additional Information (Detail) shares in Thousands, $ in Thousands, $ in Thousands |  |  | 1 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | ---
Feb. 10, 2020 TWD ($) | Feb. 10, 2020 USD ($) | Dec. 27, 2019 TWD ($) | Dec. 27, 2019 USD ($) | Dec. 31, 2013 TWD ($) | Dec. 31, 2019 USD ($) shares | Dec. 31, 2019 ¥ / shares
Disclosure Detailed Information About Others [Line Items] |  |  |  |  |  |  |
Contribution received from Environmental Protection |  |  | $ 55,062 | $ 1,841 |  |  |
Settlement patent of infringement |  |  |  |  |  | $ 5,000 |
FAFG [Member] |  |  |  |  |  |  |
Disclosure Detailed Information About Others [Line Items] |  |  |  |  |  |  |
Consideration to acquire shares |  |  |  |  |  | $ 403,125 |
Per share value | ¥ / shares |  |  |  |  |  |  | ¥ 12.81
Percentage of shareholdings auquired |  |  |  |  |  | 100.00% |
Number of shares outstanding | shares |  |  |  |  |  | 79,848 |
Issue of shares | shares |  |  |  |  |  | 25,596 |
Original Fine [Member] |  |  |  |  |  |  |
Disclosure Detailed Information About Others [Line Items] |  |  |  |  |  |  |
Administrative fine imposed |  |  |  |  | $ 102,014 |  |
New Fine [Member] |  |  |  |  |  |  |
Disclosure Detailed Information About Others [Line Items] |  |  |  |  |  |  |
Administrative fine imposed | $ 46,952 | $ 1,570 |  |  |  |  |

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