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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
	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.

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No definition available.

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- Definition

Gain on valuation of financial asset.

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No definition available.

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- Definition

Loss on valuation of financial asset.

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No definition available.

+ Details

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- Details

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