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v3.22.1

Capital Surplus - Details of Capital Surplus (Detail) $ in Thousands, $ in Thousands |  |  | 12 Months Ended
--- | --- | --- | ---
Aug. 06, 2019 TWD ($) | Mar. 07, 2019 TWD ($) | Dec. 31, 2021 TWD ($) | Dec. 31, 2021 USD ($) | Dec. 31, 2020 TWD ($) | Dec. 31, 2019 TWD ($)
Statement [LineItems] |  |  |  |  |  |
Beginning balance |  |  | $ 6,050,787 |  |  |
Share-based payments |  |  |  |  |  | $ 822
Cancellation of treasury stock | $ 962,503 | $ 962,503 |  |  |  |
Changes in associates accounted for using equity method |  |  | 4,834 |  |  |
Ending balance |  |  | 6,055,621 | $ 218,299 | $ 6,050,787 |
Capital surplus [member] |  |  |  |  |  |
Statement [LineItems] |  |  |  |  |  |
Beginning balance |  |  | 6,050,787 |  | 6,050,787 | 6,263,553
Share-based payments |  |  |  |  |  | (412)
Cancellation of treasury stock |  |  |  |  |  | (212,354)
Changes in associates accounted for using equity method |  |  | 4,834 |  |  |
Ending balance |  |  | 6,055,621 |  | 6,050,787 | 6,050,787
Capital surplus [member] | Share premium [member] |  |  |  |  |  |
Statement [LineItems] |  |  |  |  |  |
Beginning balance |  |  | 6,043,483 |  | 5,674,242 | 5,873,743
Cancellation of treasury stock |  |  |  |  |  | (199,501)
Reclassifications |  |  |  |  | 369,241 |
Ending balance |  |  | 6,043,483 |  | 6,043,483 | 5,674,242
Capital surplus [member] | Employee restricted shares [member] |  |  |  |  |  |
Statement [LineItems] |  |  |  |  |  |
Beginning balance |  |  |  |  | 369,241 | 382,506
Share-based payments |  |  |  |  |  | (412)
Cancellation of treasury stock |  |  |  |  |  | (12,853)
Reclassifications |  |  |  |  | (369,241) |
Ending balance |  |  |  |  |  | 369,241
Capital surplus [member] | Others [member] |  |  |  |  |  |
Statement [LineItems] |  |  |  |  |  |
Beginning balance |  |  | 7,304 |  | 7,304 | 7,304
Changes in associates accounted for using equity method |  |  | 4,834 |  |  |
Ending balance |  |  | $ 12,138 |  | $ 7,304 | $ 7,304

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- Definition The amount received or receivable from the issuance of the entity's shares in excess of nominal value and amounts received from other transactions involving the entity's stock or stockholders. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2021-01-01 -Paragraph 55 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2021-en-r&anchor=para_55&doctype=Standard -URIDate 2021-03-24 + Details
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- Definition The amount of treasury stock cancelled during the period. [Refer: Treasury shares] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2021-01-01 -Paragraph 106 -Subparagraph d -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2021-en-r&anchor=para_106_d&doctype=Standard -URIDate 2021-03-24 + Details
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