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Other Financial Assets and Liabilities - Summary of Valuation Gains and Losses on Derivatives Contracts (Detail) - KRW (₩) ₩ in Millions | 12 Months Ended
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Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Disclosure of detailed information about financial instruments [line items] |  |  |
Valuation gain | ₩ 154,674 | ₩ 203,961 | ₩ 0
Valuation loss | 21,213 | 7,206 | 163,710
Other comprehensive income | 85,201 | 191,570 | (113,742)
Interest rate swap [member] |  |  |
Disclosure of detailed information about financial instruments [line items] |  |  |
Valuation gain | 63 | 0 | 0
Valuation loss | 490 | 0 | 0
Other comprehensive income | 4,666 | 1 | (567)
Currency swap [member] |  |  |
Disclosure of detailed information about financial instruments [line items] |  |  |
Valuation gain | 154,611 | 203,961 | 0
Valuation loss | 20,723 | 7,206 | 161,661
Other comprehensive income | 79,781 | 191,569 | (113,175)
Currency forwards [member] |  |  |
Disclosure of detailed information about financial instruments [line items] |  |  |
Valuation gain | 0 | 0 | 0
Valuation loss | 0 | 0 | 2,049
Other comprehensive income | ₩ 754 | ₩ 0 | ₩ 0

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