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Contents of Significant Accounts - Summary of Details on Derecognition of Such Investments (Detail) - TWD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Disposed and Derecognized Investments Designated as Fair Value Through Other Comprehensive Income [Abstract]
Fair value on the date of disposal	$ 3,035,999	$ 0	$ 0
Cumulative gains (losses) reclassified to retained earnings due to derecognition	$ (1,628,388)	$ 0	$ 0

X

- Definition

The cumulative gain (loss) on disposal 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 11B
-Subparagraph c
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2023-en-r&anchor=para_11B_c&doctype=Standard
-URIDate 2023-03-23

+ Details

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X

- Definition

Disposed and derecognized investments designated as fair value through other comprehensive income.

+ References

No definition available.

+ Details

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X

- Definition

Fair value of investments measured at fair value through other comprehensive income at date of disposal.

+ References

No definition available.

+ Details

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