Percentage of ownership interest in associate.

No definition available.

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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 fair value of investments in associates if there are quoted market prices for the investment. [Refer: Associates [member]; Investments in associates reported in separate financial statements]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 12
-IssueDate 2022-03-24
-Paragraph 21
-Subparagraph b
-Clause iii
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-URIDate 2022-03-24

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- Definition

The amount of investments accounted for using the equity method. The equity method is a method of accounting whereby the investment is initially recognised at cost and adjusted thereafter for the post-acquisition change in the investor's share of net assets of the investee. The investor's profit or loss includes its share of the profit or loss of the investee. The investor's other comprehensive income includes its share of the other comprehensive income of the investee. [Refer: At cost [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 8
-IssueDate 2022-03-24
-Paragraph 24
-Subparagraph a
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=8&code=ifrs-tx-2022-en-r&anchor=para_24_a&doctype=Standard
-URIDate 2022-03-24

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2022-03-24
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-URIDate 2022-03-24

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 12
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-URIDate 2022-03-24

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- Definition

The amount of investments in associates accounted for using the equity method. [Refer: Associates [member]; Investments accounted for using equity method]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2022-03-24
-Paragraph 55
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2022-en-r&anchor=para_55&doctype=Standard
-URIDate 2022-03-24

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- Definition

The amount of investments in joint ventures accounted for using the equity method. [Refer: Joint ventures [member]; Investments accounted for using equity method]

+ References

+ Details

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- Definition

The entity's share of the other comprehensive income of associates and joint ventures accounted for using the equity method, net of tax. [Refer: Associates [member]; Investments accounted for using equity method; Joint ventures [member]; Other comprehensive income]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective on first application of IFRS 9
-Name IFRS
-Number 4
-IssueDate 2022-03-24
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- Definition

The entity's share of the profit (loss) of associates and joint ventures accounted for using the equity method. [Refer: Associates [member]; Investments accounted for using equity method; Joint ventures [member]; Profit (loss)]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 8
-IssueDate 2022-03-24
-Paragraph 28
-Subparagraph e
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=8&code=ifrs-tx-2022-en-r&anchor=para_28_e&doctype=Standard
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-Name IFRS
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- Definition

The entity's share of the total comprehensive income of associates and joint ventures accounted for using the equity method. [Refer: Associates [member]; Joint ventures [member]; Investments accounted for using equity method]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 12
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Investments Accounted for Using Equity Method - Investments in Associates (Detail) $ in Millions	12 Months Ended
	Dec. 31, 2022 TWD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 TWD ($)	Dec. 31, 2020 TWD ($)	Dec. 31, 2022 USD ($)	Mar. 31, 2022 TWD ($)	Jun. 30, 2021 TWD ($)	Mar. 31, 2021 TWD ($)
Disclosure of associates [Line Items]
Investments in associates	$ 6,939,000,000		$ 7,127,000,000
Investment in joint venture	10,000,000		10,000,000
Investments accounted for using equity method	6,949,000,000		7,137,000,000		$ 226
The Company's share of profits (loss)	442,000,000	$ 14	421,000,000	$ 244,000,000
Next Commercial Bank Co., Ltd. ("NCB") [Member]
Disclosure of associates [Line Items]
Investments in associates	3,173,000,000		3,592,000,000
Investments accounted for using equity method	$ 3,173,000,000		$ 3,592,000,000
Percentage of ownership in associates	41.90%		41.90%		41.90%
Senao Networks, Inc. ("SNI") [Member]
Disclosure of associates [Line Items]
Investments in associates	$ 1,235,000,000		$ 926,000,000
Percentage of ownership in associates	34.00%		34.00%		34.00%
Fair values based on the closing market prices	$ 3,299,000,000		$ 1,699,000,000
KingwayTek Technology Co., Ltd. ("KWT") - Listed [Member]
Disclosure of associates [Line Items]
Investments in associates	230,000,000		222,000,000
Viettel-CHT Co., Ltd. ("Viettel-CHT") [Member]
Disclosure of associates [Line Items]
Investments in associates	$ 558,000,000		$ 447,000,000
Percentage of ownership in associates	30.00%		30.00%		30.00%
Taiwan International Standard Electronics Co., Ltd. ("TISE") [Member]
Disclosure of associates [Line Items]
Investments in associates	$ 293,000,000		$ 341,000,000
Percentage of ownership in associates	40.00%		40.00%		40.00%
Chunghwa PChome Fund I Co., Ltd. ("CPFI") [Member]
Disclosure of associates [Line Items]
Investments in associates	$ 275,000,000		$ 221,000,000
Percentage of ownership in associates	50.00%		50.00%		50.00%
ST-2 Satellite Ventures Pte., Ltd. ("STS") [Member]
Disclosure of associates [Line Items]
Investments in associates	$ 247,000,000		$ 518,000,000
Percentage of ownership in associates	38.00%		38.00%		38.00%
So-net Entertainment Taiwan Limited ("So-net") [Member]
Disclosure of associates [Line Items]
Investments in associates	$ 228,000,000		$ 217,000,000
Percentage of ownership in associates	30.00%		30.00%		30.00%
WiAdvance Technology Corporation ("WATC") [Member]
Disclosure of associates [Line Items]
Investments in associates	$ 228,000,000		$ 254,000,000
KKBOX Taiwan Co., Ltd. ("KKBOXTW") [Member]
Disclosure of associates [Line Items]
Investments in associates	$ 172,000,000		$ 157,000,000
Percentage of ownership in associates	30.00%		30.00%		30.00%
Taiwan International Ports Logistics Corporation ("TIPL") [Member]
Disclosure of associates [Line Items]
Investments in associates	$ 100,000,000		$ 70,000,000
Percentage of ownership in associates	27.00%		27.00%		27.00%
CHT Infinity Singapore Pte. Ltd. ("CISG") [Member]
Disclosure of associates [Line Items]
Investments in associates	$ 63,000,000		$ 55,000,000				$ 56,000,000
Percentage of ownership in associates							40.00%
Click Force Co., Ltd. ("CF") [Member]
Disclosure of associates [Line Items]
Investments in associates	$ 41,000,000		$ 37,000,000
Percentage of ownership in associates	49.00%		49.00%		49.00%
Imedtac Co., Ltd. ("IME") [Member]
Disclosure of associates [Line Items]
Investments in associates	$ 41,000,000		$ 45,000,000
Percentage of ownership in associates	7.00%		7.00%		7.00%
AgriTalk Technology Inc. ("ATT") [Member]
Disclosure of associates [Line Items]
Investments in associates	$ 35,000,000		$ 18,000,000
Percentage of ownership in associates	29.00%		17.00%		29.00%
Baohwa Trust Co., Ltd. [Member]
Disclosure of associates [Line Items]
Investments in associates	$ 13,000,000		$ 0			$ 20,000,000
Percentage of ownership in associates	40.00%		0.00%		40.00%	40.00%
Cornerstone Ventures Co., Ltd. ("CVC") [Member]
Disclosure of associates [Line Items]
Investments in associates	$ 7,000,000		$ 7,000,000
Percentage of ownership in associates	49.00%		49.00%		49.00%
Alliance Digital Tech Co., Ltd. ("ADT") [Member]
Disclosure of associates [Line Items]
Investments in associates	$ 0		$ 0
Percentage of ownership in associates	0.00%		0.00%		0.00%
Next Commercial Bank Co., Ltd. ("NCB") [Member]
Disclosure of associates [Line Items]
Percentage of ownership in associates	42.00%		42.00%		42.00%
KingwayTek Technology Co., Ltd. ("KWT") [Member]
Disclosure of associates [Line Items]
Percentage of ownership in associates	23.00%		23.00%		23.00%
Fair values based on the closing market prices	$ 804,000,000		$ 910,000,000
WiAdvance Technology Corporation ("WATC") [Member]
Disclosure of associates [Line Items]
Investments in associates								$ 274,000,000
Percentage of ownership in associates	20.00%		20.00%		20.00%			20.33%
CHT Infinity Singapore Pte. Ltd. ("CISG") [Member]
Disclosure of associates [Line Items]
Percentage of ownership in associates	40.00%		40.00%		40.00%
Associates [member]
Disclosure of associates [Line Items]
The Company's share of profits (loss)	$ 868,000,000		$ 607,000,000	540,000,000
The Company's share of other comprehensive income (loss)	13,000,000		(6,000,000)	(8,000,000)
The Company's share of total comprehensive income (loss)	$ 881,000,000		$ 601,000,000	$ 532,000,000