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Contents of Significant Accounts - Details of Distribution (Detail) - TWD ($) $ / shares in Units, $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023
Disclosure of equity [Line Items] |  |
Appropriation of earnings, Cash dividends | $ 37,587,102 | $ 45,017,096
Cash dividends | $ 2.85 | $ 3
Legal Reserve [Member] |  |
Disclosure of equity [Line Items] |  |
Appropriation of earnings | $ 4,738,237 | $ 6,255,736
Special Reserve [member] |  |
Disclosure of equity [Line Items] |  |
Appropriation of earnings | 0 | (2,734,057)
Cash dividends [member] |  |
Disclosure of equity [Line Items] |  |
Appropriation of earnings, Cash dividends | $ 35,787,598 | $ 37,587,102

X
- Definition The amount of dividends recognised as distributions to owners of the parent. [Refer: Parent [member]] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2024-01-01 -Paragraph 106 -Subparagraph d -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2024-en-r&anchor=para_106_d&doctype=Standard -URIDate 2024-03-27 + Details
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Period Type: | duration

X
- Definition The increase (decrease) in equity resulting from transfers to a statutory reserve. [Refer: Statutory reserve] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2024-01-01 -Paragraph 106 -Subparagraph d -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2024-en-r&anchor=para_106_d&doctype=Standard -URIDate 2024-03-27 + Details
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X
- Definition The amount of cash dividends declared per share. + References No definition available. + Details
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X
- Definition Disclosure of equity [Line Items] + References No definition available. + Details
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X
- Definition Special reserve from appropriation of earnings. + References No definition available. + Details
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X
- Details
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Namespace Prefix: |
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Balance Type: |
Period Type: |

X
- Details
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Period Type: |

X
- Details
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