XML 208 R192.htm IDEA: XBRL DOCUMENT v3.21.1

Income Tax - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income tax [Line Items]
Applicable tax rate	20.00%	20.00%	20.00%	17.00%
Unappropriated earnings [Member]
Income tax [Line Items]
Applicable tax rate			5.00%	10.00%
China [Member]
Income tax [Line Items]
Applicable tax rate	25.00%	25.00%	25.00%

X

- Definition

Income tax.

+ References

No definition available.

+ Details

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Namespace Prefix:	cht_
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X

- Definition

The applicable income tax rate.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 12
-IssueDate 2020-01-01
-Paragraph 81
-Subparagraph c
-Clause ii
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=12&code=ifrs-tx-2020-en-r&anchor=para_81_c_ii&doctype=Standard
-URIDate 2020-01-01

+ Details

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X

- Details

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Namespace Prefix:
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Balance Type:
Period Type:

X

- Details

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Namespace Prefix:
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