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Other Financial Assets and Liabilities - Summary of Financial Assets Held for Trading (Detail) - Financial assets at fair value through profit or loss, classified as held for trading, category [member] - KRW (₩) ₩ in Millions | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Disclosure of detailed information about financial instruments [Line Items] |  |  |
Valuation gains |  | ₩ 33 |
Valuation losses | ₩ 3,078 |  | ₩ 2,006

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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 Valuation gains on financial assets held for trading. + References No definition available. + Details
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- Definition Valuation losses on financial assets held for trading. + References No definition available. + Details
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- Details
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