XML 157 R141.htm IDEA: XBRL DOCUMENT v3.21.1

Investment Properties - Key Assumptions and Fair Values of Investment Properties (Detail) $ in Millions, $ in Millions	Dec. 31, 2020 TWD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 TWD ($)
Disclosure of detailed information about investment property [Line Items]
Investment properties	$ 9,621	$ 343	$ 8,169
Bottom of Range [Member]
Disclosure of detailed information about investment property [Line Items]
Overall capital interest rate	0.93%	0.93%	1.03%
Profit margin ratio	12.00%	12.00%	12.00%
Capitalization rate	0.73%	0.73%	0.79%
Top of Range [Member]
Disclosure of detailed information about investment property [Line Items]
Overall capital interest rate	3.03%	3.03%	4.04%
Profit margin ratio	20.00%	20.00%	20.00%
Capitalization rate	2.20%	2.20%	1.74%
At fair value [Member]
Disclosure of detailed information about investment property [Line Items]
Investment properties	$ 22,644		$ 18,701

X

- Definition

Capital interest rate.

+ References

No definition available.

+ Details

Name:	cht_CapitalInterestRate
Namespace Prefix:	cht_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Investment property capitalization rates.

+ References

No definition available.

+ Details

Name:	cht_InvestmentPropertyCapitalizationRates
Namespace Prefix:	cht_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Profit margin ratio.

+ References

No definition available.

+ Details

Name:	cht_ProfitMarginRatio
Namespace Prefix:	cht_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

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

X

- Definition

The amount of property (land or a building - or part of a building - or both) held (by the owner or by the lessee as a right-of-use asset) to earn rentals or for capital appreciation or both, rather than for: (a) use in the production or supply of goods or services or for administrative purposes; or (b) sale in the ordinary course of business.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 40
-IssueDate 2020-01-01
-Paragraph 76
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=40&code=ifrs-tx-2020-en-r&anchor=para_76&doctype=Standard
-URIDate 2020-01-01

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 40
-IssueDate 2020-01-01
-Paragraph 79
-Subparagraph d
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=40&code=ifrs-tx-2020-en-r&anchor=para_79_d&doctype=Standard
-URIDate 2020-01-01

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2020-01-01
-Paragraph 54
-Subparagraph b
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2020-en-r&anchor=para_54_b&doctype=Standard
-URIDate 2020-01-01

+ Details

Name:	ifrs-full_InvestmentProperty
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Details

Name:	ifrs-full_RangeAxis=ifrs-full_BottomOfRangeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	ifrs-full_RangeAxis=ifrs-full_TopOfRangeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	ifrs-full_MeasurementAxis=ifrs-full_AtFairValueMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: