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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, 2018 | Dec. 31, 2017 | Jan. 01, 2017 | Dec. 31, 2016
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Total accumulated other comprehensive income | ₩ 50,158 | ₩ 30,985 | ₩ (1,432) | ₩ (1,432)
Changes in investments in associates and joint ventures [member] |  |  |  |
Total accumulated other comprehensive income | (871) | (735) |  | (10,883)
Loss on derivatives valuation [member] |  |  |  |
Total accumulated other comprehensive income | (30,474) | (3,463) |  | (34,309)
Gain on valuation of financial assets at fair value through other comprehensive income [member] |  |  |  |
Total accumulated other comprehensive income | 96,704 | 52,673 |  |
Gain of valuation on available for sale [member] |  |  |  |
Total accumulated other comprehensive income |  | 52,673 |  | 54,106
Exchange differences on translation for foreign operations [member] |  |  |  |
Total accumulated other comprehensive income | ₩ (15,201) | ₩ (17,490) |  | ₩ (10,346)

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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 2018-01-01 -Paragraph 55 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_55&doctype=Standard -URIDate 2018-03-16 + Details
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