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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, 2020 | Dec. 31, 2019 | Dec. 31, 2018
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Total accumulated other comprehensive income | ₩ 86,051 | ₩ 194,934 | ₩ 50,158
Changes in investments in associates and joint ventures [member] |  |  |
Total accumulated other comprehensive income | 16,257 | 1,556 | (871)
Loss on derivatives valuation [member] |  |  |
Total accumulated other comprehensive income | 19,809 | (7,624) |
Gain on valuation of financial assets at fair value through other comprehensive income [member] |  |  |
Total accumulated other comprehensive income | 61,438 | 211,573 | 96,704
Exchange differences on translation for foreign operations [member] |  |  |
Total accumulated other comprehensive income | ₩ (11,453) | ₩ (10,571) | ₩ (15,201)

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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 2020-01-01 -Paragraph 55 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2020-en-r&anchor=para_55&doctype=Standard -URIDate 2020-01-01 + Details
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