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Other Financial Assets and Liabilities - Additional Information (Detail) - KRW (₩) ₩ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Disclosure of detailed information about financial instruments [line items] |  |  |
Ineffective portion recognized in profit or loss cash flow hedge valuation gain | ₩ 2,711 | ₩ 4,181 | ₩ 263
Reclassified as accumulated other comprehensive income after tax | 265,087 |  |
Retained earnings of attributable to owners | 12,155,420 | 11,590,916 |
Disposal of investments in associates and joint ventures | 24 | ₩ 16,930 | ₩ 7,832
Equity Instruments Listed [member] |  |  |
Disclosure of detailed information about financial instruments [line items] |  |  |
Retained earnings of attributable to owners | 184,330 |  |
Disposal of investments in associates and joint ventures | ₩ 350,777 |  |

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