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Deferred Income Tax and Income Tax Expense - Summary of expected period of expiry for unused tax losses not recognized in deferred tax assets (Detail) - KRW (₩) ₩ in Millions | Dec. 31, 2024 | Dec. 31, 2023
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Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |
Unused tax losses for which no deferred tax asset recognised | ₩ 212,283 | ₩ 203,200
2024 [member] |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |
Unused tax losses for which no deferred tax asset recognised | 0 | 4,484
2025 [member] |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |
Unused tax losses for which no deferred tax asset recognised | 2,836 | 2,836
2026 [member] |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |
Unused tax losses for which no deferred tax asset recognised | 1,897 | 2,086
2027 [member] |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |
Unused tax losses for which no deferred tax asset recognised | 4,416 | 4,541
2028 [member] |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |
Unused tax losses for which no deferred tax asset recognised | 396 | 2,473
2029 [member] |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |
Unused tax losses for which no deferred tax asset recognised | 617 | 6,533
2030 [member] |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |
Unused tax losses for which no deferred tax asset recognised | 38 | 743
2031 [member] |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |
Unused tax losses for which no deferred tax asset recognised | 4,857 | 713
2032 [member] |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |
Unused tax losses for which no deferred tax asset recognised | 2,552 | 756
2033 [Member] |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |
Unused tax losses for which no deferred tax asset recognised | 1,455 | 0
2034 [Member] |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |
Unused tax losses for which no deferred tax asset recognised | 0 | 0
After 2035 [member] |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |
Unused tax losses for which no deferred tax asset recognised | ₩ 193,219 | ₩ 178,035

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- Definition Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table. + References No definition available. + Details
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- Definition The amount of unused tax losses for which no deferred tax asset is recognised in the statement of financial position. [Refer: Unused tax losses [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 12 -IssueDate 2024-01-01 -Paragraph 81 -Subparagraph e -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=12&code=ifrs-tx-2024-en-r&anchor=para_81_e&doctype=Standard -URIDate 2024-03-27 + Details
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