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Contents of Significant Accounts - Earnings Per Share (Detail) $ / shares in Units, $ / shares in Units, shares in Thousands, $ in Thousands, $ in Thousands | 12 Months Ended
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Dec. 31, 2024 TWD ($) $ / shares shares | Dec. 31, 2024 USD ($) $ / shares shares | Dec. 31, 2023 TWD ($) $ / shares shares | Dec. 31, 2022 TWD ($) $ / shares shares
Earnings per share-basic |  |  |  |
Net income attributable to the parent company | $ 48,779,300 | $ 1,487,627 | $ 59,688,950 | $ 89,478,805
Weighted-average number of ordinary shares for basic earnings per share (thousand shares) | 12,173,188 | 12,173,188 | 12,137,954 | 12,095,312
Earnings per share-basic (NTD) | (per share) | $ 4.01 | $ 0.12 | $ 4.92 | $ 7.4
Earnings per share-diluted |  |  |  |
Net income attributable to the parent company | $ 48,779,300 | $ 1,487,627 | $ 59,688,950 | $ 89,478,805
Weighted-average number of ordinary shares for basic earnings per share (thousand shares) | 12,173,188 | 12,173,188 | 12,137,954 | 12,095,312
Effect of dilution |  |  |  |
Restricted stocks for employees | 69,881 | 69,881 | 114,974 | 156,098
Employees' compensation | 122,400 | 122,400 | 129,196 | 238,242
Weighted-average number of ordinary shares after dilution (thousand shares) | 12,365,469 | 12,365,469 | 12,382,124 | 12,489,652
Earnings per share-diluted (NTD) | (per share) | $ 3.94 | $ 0.12 | $ 4.82 | $ 7.16

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- Definition The weighted average number of ordinary shares outstanding plus the weighted average number of ordinary shares that would be issued on the conversion of all the dilutive potential ordinary shares into ordinary shares. [Refer: Ordinary shares [member]; Weighted average [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 33 -IssueDate 2024-01-01 -Paragraph 70 -Subparagraph b -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=33&code=ifrs-tx-2024-en-r&anchor=para_70_b&doctype=Standard -URIDate 2024-03-27 + Details
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- Definition The amount of profit (loss) attributable to ordinary equity holders of the parent entity (the numerator) divided by the weighted average number of ordinary shares outstanding during the period (the denominator). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 33 -IssueDate 2024-01-01 -Paragraph 66 -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=33&code=ifrs-tx-2024-en-r&anchor=para_66&doctype=Standard -URIDate 2024-03-27 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 33 -IssueDate 2024-01-01 -Paragraph 67 -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=33&code=ifrs-tx-2024-en-r&anchor=para_67&doctype=Standard -URIDate 2024-03-27 + Details
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- Definition The amount of profit (loss) attributable to ordinary equity holders of the parent entity (the numerator), divided by the weighted average number of ordinary shares outstanding during the period (the denominator), both adjusted for the effects of all dilutive potential ordinary shares. [Refer: Ordinary shares [member]; Weighted average [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 33 -IssueDate 2024-01-01 -Paragraph 66 -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=33&code=ifrs-tx-2024-en-r&anchor=para_66&doctype=Standard -URIDate 2024-03-27 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 33 -IssueDate 2024-01-01 -Paragraph 67 -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=33&code=ifrs-tx-2024-en-r&anchor=para_67&doctype=Standard -URIDate 2024-03-27 + Details
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- Definition The profit (loss) from continuing and discontinued operations attributable to owners of the parent. [Refer: Profit (loss)] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2024-01-01 -Paragraph 81B -Subparagraph a -Clause ii -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2024-en-r&anchor=para_81B_a_ii&doctype=Standard -URIDate 2024-03-27 + Details
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- Definition The number of ordinary shares outstanding at the beginning of the period, adjusted by the number of ordinary shares bought back or issued during the period multiplied by a time-weighting factor. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 33 -IssueDate 2024-01-01 -Paragraph 70 -Subparagraph b -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=33&code=ifrs-tx-2024-en-r&anchor=para_70_b&doctype=Standard -URIDate 2024-03-27 + Details
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