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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, 2021 | Dec. 31, 2020
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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 | ₩ 106,853 | ₩ 129,680
2021 |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |
Unused tax losses for which no deferred tax asset recognised | 4,249 | 2,140
2022 |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |
Unused tax losses for which no deferred tax asset recognised | 76,133 | 80,649
2023 |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |
Unused tax losses for which no deferred tax asset recognised | 4,484 | 5,848
2024 |  |
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 | 4,867
2025 |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |
Unused tax losses for which no deferred tax asset recognised | 2,390 | 2,847
2026 |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |
Unused tax losses for which no deferred tax asset recognised | 3,419 | 9,709
2027 |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |
Unused tax losses for which no deferred tax asset recognised | 2,091 | 8,389
2028 |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |
Unused tax losses for which no deferred tax asset recognised | 2,579 | 8,426
2029 |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |
Unused tax losses for which no deferred tax asset recognised | 3,150 | 2,579
2030 |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |
Unused tax losses for which no deferred tax asset recognised | ₩ 5,522 | ₩ 4,226

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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 2021-01-01 -Paragraph 81 -Subparagraph e -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=12&code=ifrs-tx-2021-en-r&anchor=para_81_e&doctype=Standard -URIDate 2021-03-24 + Details
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