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Assets Held for Sale - Additional Information (Detail) - KRW (₩) ₩ in Millions | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Disclosure Of Assets Held For Sale [Line Items] |  |  |
Proceeds from Assets held for Sale | ₩ 83,241 | ₩ 28,834 | ₩ 9,842
Non-current assets held for sale [member] |  |  |
Disclosure Of Assets Held For Sale [Line Items] |  |  |
Impairment loss | 0 |  |
Proceeds from Assets held for Sale | ₩ 82,865 |  |

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- Definition The amount recognised as a reduction of the carrying amount of an asset or cash-generating unit to its recoverable amount. [Refer: Carrying amount [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 36 -IssueDate 2020-01-01 -Paragraph 130 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=36&code=ifrs-tx-2020-en-r&anchor=para_130_b&doctype=Standard -URIDate 2020-01-01 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 36 -IssueDate 2020-01-01 -Paragraph 130 -Subparagraph d -Clause ii -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=36&code=ifrs-tx-2020-en-r&anchor=para_130_d_ii&doctype=Standard -URIDate 2020-01-01 + Details
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- Definition The cash inflow from the disposal of non-current assets or disposal groups classified as held for sale and discontinued operations. [Refer: Discontinued operations [member]; Disposal groups classified as held for sale [member]; Non-current assets or disposal groups classified as held for sale] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 7 -IssueDate 2020-01-01 -Paragraph 16 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=7&code=ifrs-tx-2020-en-r&anchor=para_16&doctype=Standard -URIDate 2020-01-01 + Details
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- Details
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