Hedging Financial Instruments - Summary of Hedging Instrument (Details) - Forecast Purchases - forward Exchange Contract [Member] - Cash flow hedges [member] € in Millions, $ in Millions	12 Months Ended
Dec. 31, 2024 TWD ($)	Dec. 31, 2023 TWD ($)	Dec. 31, 2022 TWD ($)	Dec. 31, 2024 EUR (€)	Dec. 31, 2023 EUR (€)	Dec. 31, 2022 EUR (€)
Disclosure Of Detailed Information About Hedging Instruments [Line Items]
Change in Value of Hedged Item Used for Calculating Hedge Ineffectiveness	$ 1	$ 13	$ (21)
Accumulated Gain or Loss on Hedging Instruments in Other Equity Continuing Hedges	(1)	0	13
Accumulated Gain or Loss on Hedging Instruments in Other Equity Hedge Accounting No Longer Applied	$ 0	$ 0	$ 0
Foreign currency risk [Member]
Disclosure Of Detailed Information About Hedging Instruments [Line Items]
Currency	NT$/EUR	NT$/EUR	NT$/EUR
Contract Amount	$ 341	$ 24	$ 423	€ 10	€ 1	€ 13
Maturity Period	March 2025	March 2024	March 2023
Forward Rate	34.1	33.88	31.69
Carrying Amount of Asset	$ 1	$ 0	$ 13
Carrying Amount of Liability	2	0	0
Change in Fair Values of Hedging Instruments Used for Calculating Hedge Ineffectiveness	$ (1)	$ (13)	$ 21

Accumulated gain or loss on hedging instruments in other equity continuing hedges.

No definition available.

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- Definition

Accumulated gain or loss on hedging instruments in other equity hedge accounting no longer applied.

+ References

No definition available.

+ Details

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- Definition

Derivative contract, cross currency.

+ References

No definition available.

+ Details

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- Definition

Derivative forward rate.

+ References

No definition available.

+ Details

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- Definition

Description of derivative financial instruments maturity period.

+ References

No definition available.

+ Details

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- Definition

Gain loss on change in value of hedging instrument used as basis for recognising hedge ineffectiveness.

+ References

No definition available.

+ Details

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- Definition

The amount of financial assets classified as derivative instruments. [Refer: Financial assets; Derivatives [member]]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2024-01-01
-Paragraph 55
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2024-en-r&anchor=para_55&doctype=Standard
-URIDate 2024-03-27

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- Definition

The amount of financial liabilities classified as derivative instruments. [Refer: Financial assets; Derivatives [member]]

+ References

+ Details

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- Definition

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table.

+ References

No definition available.

+ Details

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- Definition

The gain (loss) on the change in fair value of the hedging instrument used as a basis for recognising hedge ineffectiveness. Hedge ineffectiveness is the extent to which the changes in the fair value or the cash flows of the hedging instrument are greater or less than those on the hedged item.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2024-01-01
-Paragraph 24A
-Subparagraph c
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2024-en-r&anchor=para_24A_c&doctype=Standard
-URIDate 2024-03-27

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- Definition

The nominal or face amount of a financial instrument, used to calculate payments made on that instrument.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2024-01-01
-Paragraph 112
-Subparagraph c
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2024-en-r&anchor=para_112_c&doctype=Standard
-URIDate 2024-03-27

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