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Financial Income and Costs - Summary of Details of Financial Income (Detail) - KRW (₩) ₩ in Millions | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Profit or loss [abstract] |  |  |
Interest income | ₩ 93,078 | ₩ 115,686 | ₩ 70,035
Gain on foreign currency transactions | 79,653 | 24,915 | 18,766
Gain on foreign currency translation | 225,580 | 12,165 | 11,280
Gain on settlement of derivatives |  | 8,515 | 368
Gain on valuation of derivatives | 57 | 109,436 | 141,512
Others | 7,960 | 25,422 | 30,899
Total | ₩ 406,328 | ₩ 296,139 | ₩ 272,860

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- Definition The amount of finance income that the entity does not separately disclose in the same statement or note. [Refer: Finance income] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2017-01-01 -Paragraph 112 -Subparagraph c -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_112_c&doctype=Standard -URIDate 2017-03-09 + Details
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