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Accumulated Other Comprehensive Income and Other Components of Equity - Summary of Changes in Accumulated Other Comprehensive Income (Detail) - KRW (₩) ₩ in Millions | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019
Beginning | ₩ 194,934 | ₩ 50,158
Increase /decrease | (220,314) | 189,460
Reclassified to gain or loss | 111,431 | (44,684)
Ending | 86,051 | 194,934
Changes in investments in associates and joint ventures [member] |  |
Beginning | 1,556 | (871)
Increase /decrease | 14,701 | 2,427
Ending | 16,257 | 1,556
Gain or Loss on derivatives valuation [member] |  |
Beginning | (7,624) | (30,474)
Increase /decrease | (83,998) | 67,534
Reclassified to gain or loss | 111,431 | (44,684)
Ending | 19,809 | (7,624)
Gain on valuation of financial assets at fair value through other comprehensive income [member] |  |
Beginning | 211,573 | 96,704
Increase /decrease | (150,135) | 114,869
Ending | 61,438 | 211,573
Exchange differences on translation for foreign operations [member] |  |
Beginning | (10,571) | (15,201)
Increase /decrease | (882) | 4,630
Ending | ₩ (11,453) | ₩ (10,571)

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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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- Definition The amount of other comprehensive income that will be reclassified to profit or loss, before tax. [Refer: Other comprehensive income] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2020-01-01 -Paragraph IG6 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2020-en-r&anchor=para_IG6&doctype=Implementation%20Guidance -URIDate 2020-01-01 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2020-01-01 -Paragraph 82A -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2020-en-r&anchor=para_82A&doctype=Standard -URIDate 2020-01-01 + Details
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- Definition Increase (decrease) in other comprehensive income + References No definition available. + Details
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- Details
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- Details
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