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Financial Instruments - Value Measurement Method and Significant but not Observable Inputs for the Financial Assets Classified as Fair Value Hierarchy Level 3 (Detail) - Fair value [member] - Level 3 [member] $ in Thousands, ₩ in Millions | 12 Months Ended |
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Dec. 31, 2025 KRW (₩) | Dec. 31, 2025 USD ($)
Disclosure of significant unobservable inputs used in fair value measurement of assets [line items] |  |
Volatility | 45 | 45
Bottom of range [member] |  |
Disclosure of significant unobservable inputs used in fair value measurement of assets [line items] |  |
Growth rate | 0.00% |
Discount rate | 6.00% | 6.00%
Price multiple | 0 |
Top of range [member] |  |
Disclosure of significant unobservable inputs used in fair value measurement of assets [line items] |  |
Growth rate | 1.00% |
Discount rate | 13.00% | 13.00%
Price multiple | 37.765 |
Discounted cash flow [member] |  |
Disclosure of significant unobservable inputs used in fair value measurement of assets [line items] |  |
Available-for-sale financial assets | ₩ 524,552 |
Proxy firm valuation method [member] |  |
Disclosure of significant unobservable inputs used in fair value measurement of assets [line items] |  |
Available-for-sale financial assets | 51,734 |
Binomial Option Pricing Model [Member] |  |
Disclosure of significant unobservable inputs used in fair value measurement of assets [line items] |  |
Available-for-sale financial assets | 93,831 | $ 1,827,288
Asset value approach [member] |  |
Disclosure of significant unobservable inputs used in fair value measurement of assets [line items] |  |
Available-for-sale financial assets | ₩ 589,174 |

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