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v3.25.1

Deferred Income Tax and Income Tax Expense - Summary of Tax on the Group's Profit Before Tax (Detail) - KRW (₩) ₩ in Millions | 12 Months Ended
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Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Deferred tax assets and liabilities [abstract] |  |  |
Profit before income tax expense | ₩ 571,513 | ₩ 1,302,620 | ₩ 1,891,392
Statutory income tax expense | 140,517 | 333,530 | 509,771
Tax effect |  |  |
Income not taxable for taxation purposes | (37,505) | (30,106) | (47,550)
Non-deductible expenses | 29,192 | 26,723 | 53,398
Tax credit | (42,422) | (78,459) | (54,895)
Additional payment of income taxes | 13,338 | (4,991) | 11,744
Adjustments in deferred tax from changes in tax rate | (25,012) | 564 | (41,545)
Tax effect and adjustment on consolidation |  |  |
Goodwill impairment | 52,168 | 106,010 | 5,809
Changes of out-side tax effect | (6,160) | 4,436 | 29,922
Intangible Asset impairment and amortization | (5,850) | 5,892 | 5,276
Reversal expenses of contract cost assets | 13,338 | 9,281 | (4,800)
Acquisition and disposition of businesses | 1,360 | (5,564) | 0
Others | 33,241 | (42,442) | 38,627
Income tax expense | ₩ 164,845 | ₩ 330,438 | ₩ 505,757

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