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Borrowings - Summary of Repayment of Debentures and Borrowings Including the Current Liabilities (Detail) - KRW (₩) ₩ in Millions | Dec. 31, 2024 | Dec. 31, 2023
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Disclosure of detailed information about borrowings [line items] |  |
Borrowings | ₩ 10,520,690 | ₩ 10,218,165
Long-term borrowings [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Borrowings | 931,040 | ₩ 1,356,251
Gross carrying amount [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Borrowings | 10,543,181 |
Gross carrying amount [member] | Bonds [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Borrowings | 9,162,000 |
Gross carrying amount [member] | Bonds [member] | In local currency [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Borrowings | 5,928,000 |
Gross carrying amount [member] | Bonds [member] | In foreign currency [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Borrowings | 3,234,000 |
Gross carrying amount [member] | Long-term borrowings [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Borrowings | 1,381,181 |
Gross carrying amount [member] | Long-term borrowings [member] | In local currency [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Borrowings | 1,262,305 |
Gross carrying amount [member] | Long-term borrowings [member] | In foreign currency [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Borrowings | 118,876 |
Gross carrying amount [member] | Jan.1, 2025 ~ Dec.31 2025 [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Borrowings | 3,907,592 |
Gross carrying amount [member] | Jan.1, 2025 ~ Dec.31 2025 [member] | Bonds [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Borrowings | 3,086,000 |
Gross carrying amount [member] | Jan.1, 2025 ~ Dec.31 2025 [member] | Bonds [member] | In local currency [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Borrowings | 1,763,000 |
Gross carrying amount [member] | Jan.1, 2025 ~ Dec.31 2025 [member] | Bonds [member] | In foreign currency [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Borrowings | 1,323,000 |
Gross carrying amount [member] | Jan.1, 2025 ~ Dec.31 2025 [member] | Long-term borrowings [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Borrowings | 821,592 |
Gross carrying amount [member] | Jan.1, 2025 ~ Dec.31 2025 [member] | Long-term borrowings [member] | In local currency [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Borrowings | 746,466 |
Gross carrying amount [member] | Jan.1, 2025 ~ Dec.31 2025 [member] | Long-term borrowings [member] | In foreign currency [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Borrowings | 75,126 |
Gross carrying amount [member] | Jan.1, 2026 ~ Dec.31 2026 [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Borrowings | 1,818,470 |
Gross carrying amount [member] | Jan.1, 2026 ~ Dec.31 2026 [member] | Bonds [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Borrowings | 1,668,000 |
Gross carrying amount [member] | Jan.1, 2026 ~ Dec.31 2026 [member] | Bonds [member] | In local currency [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Borrowings | 1,080,000 |
Gross carrying amount [member] | Jan.1, 2026 ~ Dec.31 2026 [member] | Bonds [member] | In foreign currency [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Borrowings | 588,000 |
Gross carrying amount [member] | Jan.1, 2026 ~ Dec.31 2026 [member] | Long-term borrowings [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Borrowings | 150,470 |
Gross carrying amount [member] | Jan.1, 2026 ~ Dec.31 2026 [member] | Long-term borrowings [member] | In local currency [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Borrowings | 119,414 |
Gross carrying amount [member] | Jan.1, 2026 ~ Dec.31 2026 [member] | Long-term borrowings [member] | In foreign currency [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Borrowings | 31,056 |
Gross carrying amount [member] | Jan.1, 2027 ~ Dec.31 2027 [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Borrowings | 1,727,831 |
Gross carrying amount [member] | Jan.1, 2027 ~ Dec.31 2027 [member] | Bonds [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Borrowings | 1,381,000 |
Gross carrying amount [member] | Jan.1, 2027 ~ Dec.31 2027 [member] | Bonds [member] | In local currency [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Borrowings | 940,000 |
Gross carrying amount [member] | Jan.1, 2027 ~ Dec.31 2027 [member] | Bonds [member] | In foreign currency [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Borrowings | 441,000 |
Gross carrying amount [member] | Jan.1, 2027 ~ Dec.31 2027 [member] | Long-term borrowings [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Borrowings | 346,831 |
Gross carrying amount [member] | Jan.1, 2027 ~ Dec.31 2027 [member] | Long-term borrowings [member] | In local currency [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Borrowings | 342,600 |
Gross carrying amount [member] | Jan.1, 2027 ~ Dec.31 2027 [member] | Long-term borrowings [member] | In foreign currency [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Borrowings | 4,231 |
Gross carrying amount [member] | Jan.1, 2028 ~ Dec.31 2028 [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Borrowings | 1,269,831 |
Gross carrying amount [member] | Jan.1, 2028 ~ Dec.31 2028 [member] | Bonds [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Borrowings | 1,250,000 |
Gross carrying amount [member] | Jan.1, 2028 ~ Dec.31 2028 [member] | Bonds [member] | In local currency [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Borrowings | 515,000 |
Gross carrying amount [member] | Jan.1, 2028 ~ Dec.31 2028 [member] | Bonds [member] | In foreign currency [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Borrowings | 735,000 |
Gross carrying amount [member] | Jan.1, 2028 ~ Dec.31 2028 [member] | Long-term borrowings [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Borrowings | 19,831 |
Gross carrying amount [member] | Jan.1, 2028 ~ Dec.31 2028 [member] | Long-term borrowings [member] | In local currency [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Borrowings | 15,600 |
Gross carrying amount [member] | Jan.1, 2028 ~ Dec.31 2028 [member] | Long-term borrowings [member] | In foreign currency [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Borrowings | 4,231 |
Gross carrying amount [member] | After Jan.1, 2029 [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Borrowings | 1,819,457 |
Gross carrying amount [member] | After Jan.1, 2029 [member] | Bonds [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Borrowings | 1,777,000 |
Gross carrying amount [member] | After Jan.1, 2029 [member] | Bonds [member] | In local currency [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Borrowings | 1,630,000 |
Gross carrying amount [member] | After Jan.1, 2029 [member] | Bonds [member] | In foreign currency [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Borrowings | 147,000 |
Gross carrying amount [member] | After Jan.1, 2029 [member] | Long-term borrowings [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Borrowings | 42,457 |
Gross carrying amount [member] | After Jan.1, 2029 [member] | Long-term borrowings [member] | In local currency [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Borrowings | 38,225 |
Gross carrying amount [member] | After Jan.1, 2029 [member] | Long-term borrowings [member] | In foreign currency [member] |  |
Disclosure of detailed information about borrowings [line items] |  |
Borrowings | ₩ 4,232 |

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