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v3.25.1

Contents of Significant Accounts - Bonds Payable - Additional Information (Detail) |  |  |  | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | --- | ---
Jul. 07, 2026 | Jul. 07, 2024 | Jul. 07, 2021 USD ($) TWD ($) | Dec. 31, 2024 USD ($) | Dec. 31, 2023 USD ($) | Dec. 31, 2024 TWD ($) $ / shares | Dec. 31, 2023 TWD ($) | Jul. 07, 2021 $ / shares
Disclosure of detailed information about bonds [Line Items] |  |  |  |  |  |  |  |
Bonds issued amount |  |  |  |  |  | $ 30,051,568,000 | $ 38,359,352,000 |
Bonds repurchased and cancelled value |  |  |  | $ 187,100,000 | $ 187,100,000 |  |  |
Number of bondholder requied redeemable outstanding exchangeable bonds |  | 0 |  |  |  |  |  |
Currency linked zero coupon exchangeable bonds maturing on July 7, 2026 [member] |  |  |  |  |  |  |  |
Disclosure of detailed information about bonds [Line Items] |  |  |  |  |  |  |  |
Bonds issued amount |  |  | $ 400,000,000 |  |  |  |  |
Per annum interest rate related to early redemption of bonds |  |  | (0.625%) |  |  |  |  |
Early Redemption Price, fixed exchange rate |  |  | 27.902 |  |  |  |  |
Percentage of principal amount, bond will be redeemable for early redemption |  | 98.14% |  |  |  |  |  |
Percentage of principal amount to redeem bonds on maturity date | 96.92% |  |  |  |  |  |  |
Effective rate of the host bonds |  |  | 3.49% |  |  |  |  |
Currency linked zero coupon exchangeable bonds maturing on July 7, 2026 [member] | Bottom of range [member] |  |  |  |  |  |  |  |
Disclosure of detailed information about bonds [Line Items] |  |  |  |  |  |  |  |
Percentage of closing stock price to quotient of early redemption amount multiplied by then exchange price divided by principal amount of bonds |  |  | 130.00% |  |  |  |  |
Percentage of the bonds that have been previously redeemed, repurchased and cancelled or exchanged, where issuer may redeem the outstanding bonds |  |  | 90.00% |  |  |  |  |
Currency linked zero coupon exchangeable bonds maturing on July 7, 2026 [member] | Common Shares of Novatek [Member] |  |  |  |  |  |  |  |
Disclosure of detailed information about bonds [Line Items] |  |  |  |  |  |  |  |
Exchange price per share | $ / shares |  |  |  |  |  | $ 506 |  | $ 731.25

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- Definition The amount of bonds issued by the entity. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2024-01-01 -Paragraph 112 -Subparagraph c -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2024-en-r&anchor=para_112_c&doctype=Standard -URIDate 2024-03-27 + Details
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