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Other Financial Assets and Liabilities - Summary of Valuation Gains and Losses on Derivatives Contracts (Detail) - KRW (₩) ₩ in Millions | 12 Months Ended
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Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Disclosure of detailed information about financial instruments [line items] |  |  |
Valuation gain | ₩ 374,974 | ₩ 45,757 | ₩ 154,674
Valuation loss | 3,793 | 162 | 21,213
Other comprehensive income | (17,817) | (30,218) | 85,201
Interest rate swap [member] |  |  |
Disclosure of detailed information about financial instruments [line items] |  |  |
Valuation gain | 76 | 48 | 63
Valuation loss | 0 | 0 | 490
Other comprehensive income | (1,044) | (2,945) | 4,666
Currency swap [member] |  |  |
Disclosure of detailed information about financial instruments [line items] |  |  |
Valuation gain | 374,898 | 45,709 | 154,611
Valuation loss | 3,793 | 162 | 20,723
Other comprehensive income | (16,773) | (27,273) | 79,781
Currency forwards [member] |  |  |
Disclosure of detailed information about financial instruments [line items] |  |  |
Valuation gain | 0 | 0 | 0
Valuation loss | 0 | 0 | 0
Other comprehensive income | ₩ 0 | ₩ 0 | ₩ 754

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