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Other Financial Assets and Liabilities - Summary of Financial Assets and Liabilities at Fair Value Through Profit or Loss (Detail) - Financial assets at fair value through profit or loss [member] - KRW (₩) ₩ in Millions | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016
Disclosure of detailed information about financial instruments [Line Items] |  |
Valuation gains |  | ₩ 470
Valuation losses | ₩ 464 | ₩ 7,654

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- Definition Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table. + References No definition available. + Details
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- Definition Gain on valuation of financial asset. + References No definition available. + Details
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- Definition Loss on valuation of financial asset. + References No definition available. + Details
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- Details
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