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Contents of Significant Accounts - Investments Accounted For Under the Equity Method - Additional Information (Detail) $ in Thousands, $ in Thousands |  | 1 Months Ended | 12 Months Ended |
--- | --- | --- | --- | ---
Jan. 06, 2023 shares | Dec. 31, 2023 TWD ($) | Jun. 30, 2023 TWD ($) | Apr. 30, 2023 TWD ($) | Dec. 31, 2023 TWD ($) | Dec. 31, 2023 USD ($) | Dec. 31, 2022 TWD ($) | Dec. 31, 2021 TWD ($) | Dec. 31, 2023 USD ($)
Investments in associates [Line Items] |  |  |  |  |  |  |  |  |
Investments accounted for using equity method for which there are published price quotations |  | $ 32,785,800 |  |  | $ 32,785,800 |  | $ 26,504,913 |  | $ 1,070,731
Proceeds from capital reduction of investments accounted for under the equity method |  |  |  |  | 1,303,106 | $ 42,557 | 0 | $ 0 |
HSUN CHIEH INVESTMENT CO., LTD. (HSUN CHIEH) [member] |  |  |  |  |  |  |  |  |
Investments in associates [Line Items] |  |  |  |  |  |  |  |  |
Investments accounted for using equity method for which there are published price quotations |  | 4,126,878 |  |  | 4,126,878 |  | 2,980,984 |  |
Proceeds from capital reduction of investments accounted for under the equity method |  |  |  | $ 343,000 |  |  |  |  |
TRIKNIGHT CAPITAL CORPORATION (TRIKNIGHT) [member] |  |  |  |  |  |  |  |  |
Investments in associates [Line Items] |  |  |  |  |  |  |  |  |
Investments accounted for using equity method for which there are published price quotations |  | 2,109,906 |  |  | 2,109,906 |  | 2,117,678 |  |
Proceeds from capital reduction of investments accounted for under the equity method |  | 560,000 | $ 400,000 |  |  |  |  |  |
UNIMICRON TECHNOLOGY CORP. (UNIMICRON) [member] |  |  |  |  |  |  |  |  |
Investments in associates [Line Items] |  |  |  |  |  |  |  |  |
Investments accounted for using equity method for which there are published price quotations |  | 13,644,560 |  |  | 13,644,560 |  | 13,285,169 |  |
UNIMICRON TECHNOLOGY CORP. (UNIMICRON) [member] | SUBTRON TECHNOLOGY CO., LTD. (SUBTRON) [member] |  |  |  |  |  |  |  |  |
Investments in associates [Line Items] |  |  |  |  |  |  |  |  |
Number of shares exchanged | shares | 23,000,000 |  |  |  |  |  |  |  |
Number of shares allotted | shares | 5,000,000 |  |  |  |  |  |  |  |
Share exchange description | 1 common share of SUBTRON to exchange 0.219 common shares of UNIMICRON |  |  |  |  |  |  |  |
Aggregated individually immaterial associates [member] |  |  |  |  |  |  |  |  |
Investments in associates [Line Items] |  |  |  |  |  |  |  |  |
Exchange differences arising from translation of the foreign entity |  |  |  |  | (3,000) |  | 103,000 | $ (30,000) |
Investments with published price quotations [member] |  |  |  |  |  |  |  |  |
Investments in associates [Line Items] |  |  |  |  |  |  |  |  |
Investments accounted for using equity method for which there are published price quotations |  | 18,008,000 |  |  | 18,008,000 |  | 15,147,000 |  |
Investments with published price quotations [member] | Fair value [member] |  |  |  |  |  |  |  |  |
Investments in associates [Line Items] |  |  |  |  |  |  |  |  |
Investments accounted for using equity method for which there are published price quotations |  | $ 53,726,000 |  |  | $ 53,726,000 |  | $ 28,416,000 |  |

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- Definition The amount of investments accounted for using the equity method. The equity method is a method of accounting whereby the investment is initially recognised at cost and adjusted thereafter for the post-acquisition change in the investor's share of net assets of the investee. The investor's profit or loss includes its share of the profit or loss of the investee. The investor's other comprehensive income includes its share of the other comprehensive income of the investee. [Refer: At cost [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 8 -IssueDate 2023-01-01 -Paragraph 24 -Subparagraph a -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=8&code=ifrs-tx-2023-en-r&anchor=para_24_a&doctype=Standard -URIDate 2023-03-23 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 12 -IssueDate 2023-01-01 -Paragraph B16 -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=12&code=ifrs-tx-2023-en-r&anchor=para_B16&doctype=Appendix&subtype=B -URIDate 2023-03-23 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2023-01-01 -Paragraph 54 -Subparagraph e -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2023-en-r&anchor=para_54_e&doctype=Standard -URIDate 2023-03-23 + Details
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