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Deferred Income Tax and Income Tax Expense - Summary of deferred tax assets and liabilities that are not recognized (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] |  |
Deductible Temporary Differences For Which No Deferred Tax Asset and Liabiities Is Recognised | ₩ 2,585,233 | ₩ 2,547,964
Taxable Temporary Differences For Which No Deferred Tax Asset and Liabilities Is Recognised | 784,170 | 495,777
Investment in subsidiaries, associates, and joint ventures |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |
Deductible Temporary Differences For Which No Deferred Tax Asset and Liabiities Is Recognised | 2,354,109 | 2,160,963
Taxable Temporary Differences For Which No Deferred Tax Asset and Liabilities Is Recognised | 784,170 | 452,286
Unused tax loss |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |
Deductible Temporary Differences For Which No Deferred Tax Asset and Liabiities Is Recognised | 106,853 | 129,680
Unused Tax credit |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |
Deductible Temporary Differences For Which No Deferred Tax Asset and Liabiities Is Recognised | 1,376 | 2,924
Others |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |
Deductible Temporary Differences For Which No Deferred Tax Asset and Liabiities Is Recognised | 122,895 | 254,397
Others |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |
Taxable Temporary Differences For Which No Deferred Tax Asset and Liabilities Is Recognised | ₩ 0 | ₩ 43,491

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