XML 154 R139.htm IDEA: XBRL DOCUMENT v3.19.1

Hedging Derivative Financial Instruments - Summary of Hedging Transaction and Reclassification Affected Comprehensive Income (Details) - Forecast Purchases - forward Exchange Contract [Member] - Cash flow hedges [member] $ in Millions	12 Months Ended
	Dec. 31, 2018 TWD ($)
Disclosure Of Reclassification Of Financial Assets [Line Items]
Hedging Gain or Loss Recognized in OCI	$ 2
Amount Reclassified to P/L and the Adjusted Line Item	$ (4)

X

- Definition

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

+ References

No definition available.

+ Details

Name:	ifrs-full_DisclosureOfReclassificationOfFinancialAssetsLineItems
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

The gain (loss) recognised in other comprehensive income on hedge ineffectiveness. [Refer: Gain (loss) on hedge ineffectiveness]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2018-01-01
-Paragraph 24C
-Subparagraph a
-Clause i
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2018-03-01&anchor=para_24C_a_i&doctype=Standard
-URIDate 2018-03-16

+ Details

Name:	ifrs-full_GainLossOnHedgeIneffectivenessRecognisedInOtherComprehensiveIncome
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

The amount of financial assets reclassified out of the at fair value through profit or loss category. [Refer: Financial assets at fair value through profit or loss]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Note Expiry date 2021-01-01
-Name IFRS
-Number 7
-IssueDate 2018-01-01
-Paragraph 12A
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2017-03-02&anchor=para_12A_a&doctype=Standard&book=b
-URIDate 2018-03-16

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Note Expiry date 2021-01-01
-Name IFRS
-Number 7
-IssueDate 2018-01-01
-Paragraph 12
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2017-03-02&anchor=para_12&doctype=Standard&book=b
-URIDate 2018-03-16

+ Details

Name:	ifrs-full_ReclassificationOutOfFinancialAssetsAtFairValueThroughProfitOrLoss
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Details

Name:	ifrs-full_ClassesOfFinancialAssetsAxis=cht_ForecastPurchasesForwardExchangeContractsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	ifrs-full_TypesOfHedgesAxis=ifrs-full_CashFlowHedgesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: