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Investments in Associates and Joint Ventures - Summary of Details of Associates (Detail) | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019
Korea Information & Technology Fund [member] |  |
Disclosure of associates [line items] |  |
Percentage of ownership | 33.30% | 33.30%
Location | Korea |
Date of financial statements | December 31 | December 31
KT-IBKC future investment fund [member] |  |
Disclosure of associates [line items] |  |
Percentage of ownership | 50.00% | 50.00%
Location | Korea |
Date of financial statements | December 31 | December 31
KT-CKP New Media Investment Fund [member] |  |
Disclosure of associates [line items] |  |
Percentage of ownership |  | 49.70%
Location | Korea |
Date of financial statements | December 31 | December 31
K Bank Inc. [member] |  |
Disclosure of associates [line items] |  |
Percentage of ownership | 34.00% | 10.00%
Location | Korea |
Date of financial statements | December 31 | December 31
Hyundai Robotics Co., Ltd. [member] |  |
Disclosure of associates [line items] |  |
Percentage of ownership | 10.00% |
Location | Korea |
Date of financial statements | December 31 | December 31

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- Definition The country in which an associate of the entity is incorporated. [Refer: Associates [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 27 -IssueDate 2020-01-01 -Paragraph 16 -Subparagraph b -Clause ii -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=27&code=ifrs-tx-2020-en-r&anchor=para_16_b_ii&doctype=Standard -URIDate 2020-01-01 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 27 -IssueDate 2020-01-01 -Paragraph 17 -Subparagraph b -Clause ii -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=27&code=ifrs-tx-2020-en-r&anchor=para_17_b_ii&doctype=Standard -URIDate 2020-01-01 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 12 -IssueDate 2020-01-01 -Paragraph 21 -Subparagraph a -Clause iii -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=12&code=ifrs-tx-2020-en-r&anchor=para_21_a_iii&doctype=Standard -URIDate 2020-01-01 + Details
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- 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
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- Definition The proportion of ownership interest in an associate attributable to the entity. [Refer: Associates [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 27 -IssueDate 2020-01-01 -Paragraph 17 -Subparagraph b -Clause iii -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=27&code=ifrs-tx-2020-en-r&anchor=para_17_b_iii&doctype=Standard -URIDate 2020-01-01 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 27 -IssueDate 2020-01-01 -Paragraph 16 -Subparagraph b -Clause iii -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=27&code=ifrs-tx-2020-en-r&anchor=para_16_b_iii&doctype=Standard -URIDate 2020-01-01 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 12 -IssueDate 2020-01-01 -Paragraph 21 -Subparagraph a -Clause iv -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=12&code=ifrs-tx-2020-en-r&anchor=para_21_a_iv&doctype=Standard -URIDate 2020-01-01 + Details
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- Details
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- Details
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- Details
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- Details
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- Details
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