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Financial Risk and Fair Value Disclosures - Maturity Profile of Financial Liabilities Based on Contractual Undiscounted Payments and Contractual Maturity (Parenthetical) (Detail) - TWD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Disclosure Of Maturity Analysis For Non-derivative And Derivative Financial Liabilities [Line Items]
Investments in equity instruments designated at fair value through other comprehensive income	$ 5,753	$ 3,213
Unsecured Exchangeable Bonds [Member]
Disclosure Of Maturity Analysis For Non-derivative And Derivative Financial Liabilities [Line Items]
Redemption of bonds at put price at the option of bondholders, date	Jul. 07, 2024
Redemption of bonds at put price at the option of bondholders percentage of principal amount	98.14%

X

- 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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- Definition

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- Definition

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- Definition

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