Disclosure of fair value measurement of assets and liabilities.

No definition available.

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- Definition

The amount of derivative financial assets held for hedging. [Refer: Derivative financial assets]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2021-01-01
-Paragraph 55
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2021-en-r&anchor=para_55&doctype=Standard
-URIDate 2021-03-24

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- Definition

The amount of derivative financial liabilities held for hedging. [Refer: Derivative financial liabilities]

+ References

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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 2021-01-01
-Paragraph 11A
-Subparagraph c
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2021-en-r&anchor=para_11A_c&doctype=Standard
-URIDate 2021-03-24

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2021-01-01
-Paragraph 8
-Subparagraph h
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2021-en-r&anchor=para_8_h&doctype=Standard
-URIDate 2021-03-24

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- Definition

The amount of financial assets that are measured at fair value and for which gains (losses) are recognised in profit or loss. A financial asset shall be measured at fair value through profit or loss unless it is measured at amortised cost or at fair value through other comprehensive income. A gain (loss) on a financial asset measured at fair value shall be recognised in profit or loss unless it is part of a hedging relationship, it is an investment in an equity instrument for which the entity has elected to present gains and losses in other comprehensive income or it is a financial asset measured at fair value through other comprehensive income. [Refer: At fair value [member]; Financial assets]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2021-01-01
-Paragraph 8
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2021-en-r&anchor=para_8_a&doctype=Standard
-URIDate 2021-03-24

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- Definition

The amount of financial liabilities at fair value through profit or loss that meet the definition of held for trading. A financial liability is classified as held for trading if: (a) it is acquired or incurred principally for the purpose of selling or repurchasing it in the near term; (b) on initial recognition it is part of a portfolio of identified financial instruments that are managed together and for which there is evidence of a recent actual pattern of short-term profit-taking; or (c) it is a derivative (except for a derivative that is a financial guarantee contract or a designated and effective hedging instrument). [Refer: Financial liabilities at fair value through profit or loss]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2021-01-01
-Paragraph 8
-Subparagraph e
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2021-en-r&anchor=para_8_e&doctype=Standard
-URIDate 2021-03-24

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Fair Value Information - Financial Instruments Measured at Fair Value on a Recurring Basis (Detail) $ in Millions, $ in Millions	Dec. 31, 2021 TWD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 TWD ($)
Disclosure Of Fair Value Measurement Of Assets And Liabilities [Line Items]
Financial liabilities at FVTPL derivative	$ 6		$ 0
Hedging financial liabilities	8	$ 0	0
Fair value on a recurring basis [Member]
Disclosure Of Fair Value Measurement Of Assets And Liabilities [Line Items]
Financial assets at FVTPL	912		687
Hedging financial assets			2
Financial assets at FVOCI	3,616		7,193
Hedging financial liabilities	8
Fair value on a recurring basis [Member] \| Derivatives [Member]
Disclosure Of Fair Value Measurement Of Assets And Liabilities [Line Items]
Financial assets at FVTPL			2
Fair value on a recurring basis [Member] \| Listed stocks [Member]
Disclosure Of Fair Value Measurement Of Assets And Liabilities [Line Items]
Financial assets at FVTPL	3		8
Financial assets at FVOCI	459		2,754
Fair value on a recurring basis [Member] \| Non-listed stocks [Member]
Disclosure Of Fair Value Measurement Of Assets And Liabilities [Line Items]
Financial assets at FVTPL	885		677
Financial assets at FVOCI	3,157		4,439
Fair value on a recurring basis [Member] \| Limited Partnership [Member]
Disclosure Of Fair Value Measurement Of Assets And Liabilities [Line Items]
Financial assets at FVTPL	24
Fair value on a recurring basis [Member] \| Level 1 [Member]
Disclosure Of Fair Value Measurement Of Assets And Liabilities [Line Items]
Financial assets at FVTPL	3		8
Financial assets at FVOCI	459		2,754
Fair value on a recurring basis [Member] \| Level 1 [Member] \| Listed stocks [Member]
Disclosure Of Fair Value Measurement Of Assets And Liabilities [Line Items]
Financial assets at FVTPL	3		8
Financial assets at FVOCI	459		2,754
Fair value on a recurring basis [Member] \| Level 2 [Member]
Disclosure Of Fair Value Measurement Of Assets And Liabilities [Line Items]
Financial assets at FVTPL			2
Hedging financial assets			2
Hedging financial liabilities	8
Fair value on a recurring basis [Member] \| Level 2 [Member] \| Derivatives [Member]
Disclosure Of Fair Value Measurement Of Assets And Liabilities [Line Items]
Financial assets at FVTPL			2
Fair value on a recurring basis [Member] \| Level 3 [Member]
Disclosure Of Fair Value Measurement Of Assets And Liabilities [Line Items]
Financial assets at FVTPL	909		677
Financial assets at FVOCI	3,157		4,439
Fair value on a recurring basis [Member] \| Level 3 [Member] \| Non-listed stocks [Member]
Disclosure Of Fair Value Measurement Of Assets And Liabilities [Line Items]
Financial assets at FVTPL	885		677
Financial assets at FVOCI	3,157		4,439
Fair value on a recurring basis [Member] \| Level 3 [Member] \| Limited Partnership [Member]
Disclosure Of Fair Value Measurement Of Assets And Liabilities [Line Items]
Financial assets at FVTPL	24
Fair value on a recurring basis [Member] \| Derivatives [Member]
Disclosure Of Fair Value Measurement Of Assets And Liabilities [Line Items]
Financial liabilities at FVTPL derivative	6		0
Fair value on a recurring basis [Member] \| Derivatives [Member] \| Level 2 [Member]
Disclosure Of Fair Value Measurement Of Assets And Liabilities [Line Items]
Financial liabilities at FVTPL derivative	$ 6		$ 0