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Share Capital and Capital Surplus - Summary of Capital Surplus (Detail) - KRW (₩) ₩ in Millions | Dec. 31, 2025 | Dec. 31, 2024
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Statement of changes in equity [abstract] |  |
Share premium | ₩ 463,825 | ₩ 463,825
Gain on disposal of treasury shares | 808,994 | 808,994
Other capital surplus | 421,753 | 385,531
Capital surplus | ₩ 1,694,572 | ₩ 1,658,350

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- Definition The amount received or receivable from the issuance of the entity's shares in excess of nominal value and amounts received from other transactions involving the entity's stock or stockholders. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Note Expiry date 2027-01-01 -Name IAS -Number 1 -IssueDate 2025-01-01 -Paragraph 55 -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2025-en-b&anchor=para_55&doctype=Standard -URIDate 2025-03-27 + Details
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- Definition The amount received or receivable from the issuance of the entity's shares in excess of nominal value. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Note Effective 2027-01-01 -Name IFRS -Number 19 -IssueDate 2025-01-01 -Paragraph B9 -Subparagraph f -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_B9_f&doctype=Appendix&subtype=B -URIDate 2025-03-27 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Note Expiry date 2027-01-01 -Name IAS -Number 1 -IssueDate 2025-01-01 -Paragraph 78 -Subparagraph e -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2025-en-b&anchor=para_78_e&doctype=Standard -URIDate 2025-03-27 + Details
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- References No definition available. + Details
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- Definition Gain on Disposal of Treasury Share + References No definition available. + Details
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- Definition Other capital surplus (deficit). + References No definition available. + Details
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