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Financial Income and Costs - Summary of Details of Financial Expense (Detail) - KRW (₩) ₩ in Millions | 12 Months Ended
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Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Disclosure Of Finance Income [line items] |  |  |
Interest expenses | ₩ 268,225 | ₩ 296,874 | ₩ 302,464
Loss on foreign currency transactions | 30,267 | 49,156 | 40,303
Loss on foreign currency translation | 93,977 | 72,642 | 12,239
Loss on settlement of derivatives | 20 |  | 58,569
Loss on valuation of derivatives | 15,867 | 2,045 | 209,582
Others | 2,277 | 1,124 | 1,010
Total | 421,931 | 435,659 | 644,531
Loans and receivables [member] |  |  |
Disclosure Of Finance Income [line items] |  |  |
Loss on disposal of trade receivables | ₩ 11,298 | ₩ 13,818 | 20,355
Available-for-sale [member] |  |  |
Disclosure Of Finance Income [line items] |  |  |
Impairment loss on available-for-sale financial assets |  |  | ₩ 9

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- Definition The amount of costs associated with financing activities of the entity. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2019-01-01 -Paragraph 82 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2019-en-r&anchor=para_82_b&doctype=Standard -URIDate 2019-03-27 + Details
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- Definition The gains (losses) on loans and receivables. [Refer: Loans and receivables] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Note Expiry date 2021-01-01 -Name IFRS -Number 7 -IssueDate 2019-01-01 -Paragraph 20 -Subparagraph a -Clause iv -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2017-en-b&anchor=para_20_a_iv&doctype=Standard&book=b -URIDate 2019-03-27 + Details
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- Definition The amount of impairment loss on financial assets. [Refer: Financial assets; Impairment loss] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Note Expiry date 2021-01-01 -Name IFRS -Number 7 -IssueDate 2019-01-01 -Paragraph 20 -Subparagraph e -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2017-en-b&anchor=para_20_e&doctype=Standard&book=b -URIDate 2019-03-27 + Details
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- Definition The amount of expense arising from interest. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 8 -IssueDate 2019-01-01 -Paragraph 23 -Subparagraph d -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=8&code=ifrs-tx-2019-en-r&anchor=para_23_d&doctype=Standard -URIDate 2019-03-27 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 8 -IssueDate 2019-01-01 -Paragraph 28 -Subparagraph e -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=8&code=ifrs-tx-2019-en-r&anchor=para_28_e&doctype=Standard -URIDate 2019-03-27 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 12 -IssueDate 2019-01-01 -Paragraph B13 -Subparagraph f -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=12&code=ifrs-tx-2019-en-r&anchor=para_B13_f&doctype=Appendix&subtype=B -URIDate 2019-03-27 + Details
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- Definition The losses resulting from changes in the fair value of derivatives recognised in profit or loss. [Refer: Derivatives [member]] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2019-01-01 -Paragraph 85 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2019-en-r&anchor=para_85&doctype=Standard -URIDate 2019-03-27 + Details
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- Definition The net loss arising from foreign exchange differences. [Refer: Foreign exchange gain (loss)] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 21 -IssueDate 2019-01-01 -Paragraph 52 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=21&code=ifrs-tx-2019-en-r&anchor=para_52_a&doctype=Standard -URIDate 2019-03-27 + Details
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- Definition The amount of finance costs that the entity does not separately disclose in the same statement or note. [Refer: Finance costs] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2019-01-01 -Paragraph 112 -Subparagraph c -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2019-en-r&anchor=para_112_c&doctype=Standard -URIDate 2019-03-27 + Details
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