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Investments in Associates and Joint Ventures - Summary of Changes in Investments in Associates and Joint Ventures (Detail) - KRW (₩) ₩ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019
Disclosure Of Associates And Joint Ventures [Line Items] |  |
Beginning | ₩ 267,660 | ₩ 272,407
Acquisition (Disposal) | 273,277 | 13,021
Share of net profit from associates and joint ventures | 18,320 | (3,252)
Others | (1,376) | (14,516)
Ending | 557,881 | 267,660
Korea Information & Technology Fund [member] |  |
Disclosure Of Associates And Joint Ventures [Line Items] |  |
Beginning | 163,975 | 148,255
Share of net profit from associates and joint ventures | 12,205 | 17,956
Others | (6,025) | (2,236)
Ending | 170,155 | 163,975
KT-SB Venture Investment Fund [member] |  |
Disclosure Of Associates And Joint Ventures [Line Items] |  |
Beginning |  | 4,470
Acquisition (Disposal) |  | (4,470)
KT-CKP New Media Investment Fund [member] |  |
Disclosure Of Associates And Joint Ventures [Line Items] |  |
Beginning | 134 | 281
Acquisition (Disposal) | (134) | (174)
Share of net profit from associates and joint ventures |  | 27
Ending |  | 134
Hyundai Robotics Co., Ltd. [member] |  |
Disclosure Of Associates And Joint Ventures [Line Items] |  |
Acquisition (Disposal) | 50,000 |
Share of net profit from associates and joint ventures | (64) |
Others | 1,000 |
Ending | 50,936 |
Others [Member] |  |
Disclosure Of Associates And Joint Ventures [Line Items] |  |
Beginning | 44,293 | 56,785
Acquisition (Disposal) | 28,400 | (7,867)
Share of net profit from associates and joint ventures | 34,298 | 7,241
Others | 5,337 | (11,866)
Ending | 112,328 | 44,293
KT-IBKC future investment fund [member] |  |
Disclosure Of Associates And Joint Ventures [Line Items] |  |
Beginning | 14,100 | 9,961
Acquisition (Disposal) |  | 3,750
Share of net profit from associates and joint ventures | 2,090 | 389
Ending | 16,190 | 14,100
K Bank Inc. [member] |  |
Disclosure Of Associates And Joint Ventures [Line Items] |  |
Beginning | 45,158 | 52,655
Acquisition (Disposal) | 195,011 | 21,782
Share of net profit from associates and joint ventures | (30,209) | (28,865)
Others | (1,688) | (414)
Ending | ₩ 208,272 | ₩ 45,158

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- Definition The amount of investments in subsidiaries, joint ventures and associates in an entity's separate financial statements. [Refer: Associates [member]; Joint ventures [member]; Subsidiaries [member]; Investments in subsidiaries] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 27 -IssueDate 2020-01-01 -Paragraph 10 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=27&code=ifrs-tx-2020-en-r&anchor=para_10&doctype=Standard -URIDate 2020-01-01 + Details
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- Definition The entity's share of the profit (loss) from continuing operations of associates and joint ventures accounted for using the equity method. [Refer: Associates [member]; Continuing operations [member]; Investments accounted for using equity method; Joint ventures [member]; Profit (loss) from continuing operations] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 12 -IssueDate 2020-01-01 -Paragraph B16 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=12&code=ifrs-tx-2020-en-r&anchor=para_B16_a&doctype=Appendix&subtype=B -URIDate 2020-01-01 + Details
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- Definition Acquisition (disposal) of investments in subsidiaries, joint ventures and associates. + References No definition available. + Details
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