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Share Capital and Capital Surplus - Summary of Share Capital (Parenthetical) (Detail) - KRW (₩) ₩ in Millions | 12 Months Ended |  |  |
--- | --- | --- | --- | ---
Dec. 31, 2025 | Feb. 19, 2025 | Dec. 31, 2024 | Dec. 31, 2023
Disclosure of classes of share capital [line items] |  |  |  |
Total shares of ADRs outstanding | 75,620,779 |  | 75,620,779 | 75,876,207
Retirement of treasury stock | 15,547,673 |  |  |
Forfeiture of shares |  | 1,691,425 |  |
Aggregate par value of common stock issued | ₩ 77,738 |  |  |
ADRs [member] |  |  |  |
Disclosure of classes of share capital [line items] |  |  |  |
Total shares of ADRs outstanding | 9,159,020 |  |  |
Total shares of ADRs outstanding, equivalent common stock shares | 2,289,755 |  |  |

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