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Accumulated Other Comprehensive Income and Other Components of Equity - Summary of Accumulated Other Comprehensive Income (Detail) - KRW (₩) ₩ in Millions | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
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Total accumulated other comprehensive income | ₩ 30,985 | ₩ (1,432) | ₩ 13,870
Changes in investments in associates and joint ventures [member] |  |  |
Total accumulated other comprehensive income | (735) | (10,883) | (10,312)
Loss on derivatives valuation [member] |  |  |
Total accumulated other comprehensive income | (3,463) | (34,309) | (23,234)
Gain of valuation on available for sale [member] |  |  |
Total accumulated other comprehensive income | 52,673 | 54,106 | 52,415
Foreign currency translation adjustment [Member] |  |  |
Total accumulated other comprehensive income | ₩ (17,490) | ₩ (10,346) | ₩ (4,999)

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- Definition The amount of accumulated items of income and expense (including reclassification adjustments) that are not recognised in profit or loss as required or permitted by other IFRSs. [Refer: IFRSs [member]; Other comprehensive income] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2017-01-01 -Paragraph 55 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_55&doctype=Standard -URIDate 2017-03-09 + Details
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