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Financial Risk Management - Summary of Exposures to Risks, Effects on Profit before Income Tax and Shareholders' Equity (Detail) - KRW (₩) ₩ in Millions | 12 Months Ended
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Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
10% strengthening in foreign exchange rate [member] |  |  |
Disclosure of detailed information about financial instruments [line items] |  |  |
Fluctuation of foreign exchange rate | 10.00% | 10.00% | 10.00%
Impact on profit before income tax | ₩ (5,841) | ₩ (3,433) | ₩ 25,220
Impact on equity | ₩ (15,836) | ₩ 8,692 | ₩ 36,961
10% weakening in foreign exchange rate [member] |  |  |
Disclosure of detailed information about financial instruments [line items] |  |  |
Fluctuation of foreign exchange rate | 10.00% | 10.00% | 10.00%
Impact on profit before income tax | ₩ 5,841 | ₩ 3,433 | ₩ (25,220)
Impact on equity | ₩ 15,836 | ₩ (8,692) | ₩ (36,961)
10% percentage increase in market equity price [member] |  |  |
Disclosure of detailed information about financial instruments [line items] |  |  |
Fluctuation of price | 10.00% | 10.00% | 10.00%
Impact on profit before income tax | ₩ 2,660 | ₩ 2,000 | ₩ 2,811
Impact on equity | ₩ 113,948 | ₩ 4,588 | ₩ 3,472
10% decrease in market equity price [member] |  |  |
Disclosure of detailed information about financial instruments [line items] |  |  |
Fluctuation of price | 10.00% | 10.00% | 10.00%
Impact on profit before income tax | ₩ (2,660) | ₩ (2,000) | ₩ (2,811)
Impact on equity | ₩ (113,948) | ₩ (4,588) | ₩ (3,472)
100 basis point increase in market interest rate [Member] |  |  |
Disclosure of detailed information about financial instruments [line items] |  |  |
Fluctuation of interest rate | 1.00% | 1.00% | 1.00%
Impact on profit before income tax | ₩ 635 | ₩ 753 | ₩ 973
Impact on equity | ₩ (2,045) | ₩ 5,549 | ₩ 18,584
100 basis point decrease in market interest rate [Member] |  |  |
Disclosure of detailed information about financial instruments [line items] |  |  |
Fluctuation of interest rate | 1.00% | 1.00% | 1.00%
Impact on profit before income tax | ₩ (669) | ₩ (731) | ₩ (973)
Impact on equity | ₩ 2,100 | ₩ (5,675) | ₩ (19,377)

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