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v3.21.1

Deferred Income Tax and Income Tax Expense - Summary of Tax on the Group's Profit Before Tax (Detail) - KRW (₩) ₩ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Deferred tax assets and liabilities [abstract] |  |  |
Profit before income tax expense | ₩ 1,031,605 | ₩ 1,015,928 | ₩ 1,033,977
Statutory income tax expense | 273,329 | 269,018 | 273,982
Tax effect |  |  |
Income not taxable for taxation purposes | (24,657) | (1,265) | (85,322)
Non-deductible expenses | 31,741 | 19,543 | 18,126
Tax credit | (47,056) | (39,190) | (20,319)
Additional payment of income taxes | 429 | 3,832 | 11,439
Tax effect and adjustment on consolidation |  |  |
Goodwill impairment |  | 159 | 137
Eliminated dividend income form subsidiaries | 20,682 | 21,917 | 31,966
Changes of out-side tax effect | 38,552 | 13,539 | 618
Tax effect of investment in kind |  |  | 82,820
Intangible Asset impairment and amortization | 3,790 | 14,052 |
Reversal expenses of contract cost assets | (6,643) | 11,213 |
Others | (4,818) | 7,242 | 1,118
Income tax expense | ₩ 285,349 | ₩ 320,060 | ₩ 314,565

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