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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
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

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+ References

No definition available.

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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

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