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Contents of Significant Accounts - Summary of Fair Value of Each Investment in Equity Instrument (Detail) - TWD ($) $ in Thousands | Dec. 31, 2023 | Dec. 31, 2022
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Disclosure of fair value of investments in equity instruments designated at fair value through other comprehensive income [line items] |  |
Fair value of investments in equity instruments | $ 5,753,000 | $ 3,213,000
SILICON INTEGRATED SYSTEMS CORP. [member] |  |
Disclosure of fair value of investments in equity instruments designated at fair value through other comprehensive income [line items] |  |
Fair value of investments in equity instruments | 0 | 2,316,197
UNIMICRON HOLDING LIMITED [member] |  |
Disclosure of fair value of investments in equity instruments designated at fair value through other comprehensive income [line items] |  |
Fair value of investments in equity instruments | 2,514,120 | 2,847,385
ITE TECH. INC. [member] |  |
Disclosure of fair value of investments in equity instruments designated at fair value through other comprehensive income [line items] |  |
Fair value of investments in equity instruments | 2,100,977 | 1,023,266
NOVATEK MICROELECTRONICS CORP. (NOVATEK) [member] |  |
Disclosure of fair value of investments in equity instruments designated at fair value through other comprehensive income [line items] |  |
Fair value of investments in equity instruments | 8,501,851 | 5,188,267
SHIN-ETSU HANDOTAI TAIWAN CO., LTD. [member] |  |
Disclosure of fair value of investments in equity instruments designated at fair value through other comprehensive income [line items] |  |
Fair value of investments in equity instruments | 548,205 | 580,335
MTIC HOLDINGS PTE. LTD. [member] |  |
Disclosure of fair value of investments in equity instruments designated at fair value through other comprehensive income [line items] |  |
Fair value of investments in equity instruments | 175,063 | 182,547
CHIPBOND TECHNOLOGY CORPORATION [member] |  |
Disclosure of fair value of investments in equity instruments designated at fair value through other comprehensive income [line items] |  |
Fair value of investments in equity instruments | $ 3,843,744 | $ 3,051,603

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- Definition The amount of investments in equity instruments that the entity has designated at fair value through other comprehensive income. [Refer: At fair value [member]; Other comprehensive income] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2023-01-01 -Paragraph 11A -Subparagraph c -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2023-en-r&anchor=para_11A_c&doctype=Standard -URIDate 2023-03-23 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2023-01-01 -Paragraph 8 -Subparagraph h -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2023-en-r&anchor=para_8_h&doctype=Standard -URIDate 2023-03-23 + Details
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