Investments in subsidiaries joint ventures and associates fair value disclosure.

No definition available.

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- Definition

Noncurrent financial assets at fair value through other comprehensive income.

+ References

No definition available.

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- Definition

Private placement.

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No definition available.

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- Definition

The amount of dividends received.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

The amount investment funds contribute to the fair value of defined benefit plan assets. [Refer: Plan assets, at fair value; Defined benefit plans [member]; Investment funds [member]]

+ References

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- Definition

The amount of other comprehensive income, net of tax, related to gains (losses) from changes in the fair value of investments in equity instruments that the entity has designated at fair value through other comprehensive income applying paragraph 5.7.5 of IFRS 9. [Refer: Other comprehensive income]

+ References

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Financial Assets at Fair Value through Other Comprehensive Income Noncurrent - Additional Information (Detail) - TWD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Oct. 31, 2021	Aug. 31, 2021	Jul. 31, 2021
Disclosure of financial assets [Line Items]
Unrealized gains (losses) on financial assets at FVOCI		$ (0.1)	$ 60.0
Dividends received	$ 167.0	157.0	154.0
UUPON Inc. (UUPON) [Member]
Disclosure of financial assets [Line Items]
Fair value amount		$ 0.2		$ 1.0
China Airlines, Ltd. [Member]
Disclosure of financial assets [Line Items]
Fair value amount			2,636.0
Cotech Engineering Fuzhou Corp. [Member]
Disclosure of financial assets [Line Items]
Fair value amount			$ 4.0
AgriTalk Technology Inc. ("ATT") [Member]
Disclosure of financial assets [Line Items]
Investments reclassified from financial asset at FVOCI to investments in associates at fair value						$ 19.0
Imedtac Co., Ltd. ("IME") [Member]
Disclosure of financial assets [Line Items]
Investments reclassified from financial asset at FVOCI to investments in associates at fair value					$ 45.0
PChome Online Inc.
Disclosure of financial assets [Line Items]
Private placement				$ 200.0