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Commitments and Contingencies - Additional Information (Detail) ₩ in Thousands	12 Months Ended
	Mar. 09, 2018 KRW (₩)	Dec. 31, 2017 KRW (₩) Lawsuits	Dec. 31, 2016 KRW (₩)
Commitments and contingencies [abstract]
Severally liable for reimbursement		₩ 4,328,000
Number of lawsuits | Lawsuits		187
Litigation settlement claim amount		₩ 112,639,000	₩ 77,461,000
Litigation provision		18,306,000
Compensatory damages awarded to plaintiff	₩ 748,564,000
Interest on compensatory damages awarded	₩ 287,673,150
Interest rate on compensatory damages awarded delay	9.00%
Period for which compensatory damage settlement agreed	December 1, 2013 to March 9, 2018
Collaterally guarantees the debt		₩ 9,000,000
New town development consortium percentage of ownership interest		2.50%
Contract amount not yet recognized as liabilities		₩ 622,059,000	₩ 489,753,000

X

- Definition

The amount expected to be reimbursed by another party on expenditures to settle other provisions. [Refer: Other provisions]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

The amount of guarantees or collateral provided by the entity in related party transactions. [Refer: Guarantees [member]; Related parties [member]]

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-Name IAS
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Acquisition contract agreement not yet recognized as liabilities.

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Commitments and contingencies [abstract]

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- Definition

Gains losses on litigation provisions.

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- Definition

Guarantee interest percentage.

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- Definition

Litigation Settlement Interest 1

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- Definition

Litigation Settlement, Interest Rate

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- Definition

Litigation settlements claim amount.

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- Definition

Loss Contingency Damages Awarded Value 1

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Number of law suits faced.

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- Definition

Period of delay recorded in compensatory award

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