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Investments in Associates and Joint Ventures - Additional Information (Detail) - KRW (₩) ₩ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Disclosure of associates [abstract]
Loss from associates and joint ventures not recognized	₩ 4,391	₩ 1,354	₩ 601
Accumulated comprehensive loss of associates and joint ventures not recognized	₩ 17,045	₩ 18,096	₩ 51,597

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No definition available.

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- Definition

The cumulative amount of the unrecognised share of losses of associates and joint ventures if the entity has stopped recognising its share of losses when applying the equity method.

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No definition available.

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- Definition

The amount of the unrecognised share of associate and joint venture losses if the entity has stopped recognising its share of losses when applying the equity method.

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No definition available.

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