Debt - Schedule of Long-Term Debt (Details) - KRW (₩) ₩ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Total	₩ 716,400	₩ 930,000
Less: current portion	(205,610)	(245,240)
Total long-term debt less current portion	510,790	684,760
Long Term Debt One [Member]
Total	416,400	500,000
Long Term Debt Two [Member]
Total	200,000	200,000
Long Term Debt Three [Member]
Total	100,000
Long Term Debt Four [Member]
Total		₩ 230,000

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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