Carrying value as of the balance sheet date of payments made in excess of existing cash balances, which will be honored by the bank but reflected as a loan to the entity. Overdrafts generally have a very short time frame for correction or repayment and are therefore more similar to short-term bank financing than trade financing.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.20)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section 45
-Paragraph 10
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The value of the collateral (typically cash) that the entity receives in a financing transaction in exchange for securities lent. This item represents a liability in the financial statements of the lender of the securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(m)(1)(i)(A)(ii))
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Contractual interest rate for funds borrowed, under the debt agreement.

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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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.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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The cash inflow from a borrowing having initial term of repayment within one year or the normal operating cycle, if longer.

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The cash outflow for a borrowing having initial term of repayment within one year or the normal operating cycle, if longer.

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Debt (Details Narrative) - KRW (₩) ₩ in Thousands												12 Months Ended
Debt (Details Narrative) - KRW (₩) ₩ in Thousands	Nov. 03, 2017	Sep. 29, 2017	Aug. 04, 2017	Apr. 19, 2017	Apr. 18, 2017	Jul. 18, 2016	Dec. 16, 2015	Nov. 04, 2015	Oct. 08, 2015	Jun. 02, 2015	Mar. 23, 2012	Dec. 31, 2017	Dec. 31, 2016
Short-term borrowings												₩ 1,459,992	₩ 1,898,665
Repayments of short term borrowings												1,302,830	2,588,489
Long term debt												930,000	850,000
Short Term Borrowings One [Member] \| Refinancing Agreement [Member]
Repayments of short term borrowings		₩ 26,000
Short Term Borrowings One [Member] \| Kookmin Bank [Member]
Short-term borrowings									₩ 260,000			₩ 234,000	₩ 260,000
Debt instrument maturity date									Oct. 02, 2018
Debt instrument, rate of interest												4.70%	2.95%
Short Term Borrowings Two [Member] \| Refinancing Agreement [Member]
Repayments of short term borrowings	₩ 26,000
Short Term Borrowings Two [Member] \| Kookmin Bank [Member]
Short-term borrowings								₩ 260,000				₩ 234,000	₩ 260,000
Debt instrument maturity date								Nov. 02, 2018
Debt instrument, rate of interest												5.05%	2.95%
Short Term Borrowings Three [Member] \| Shinhan Bank [Member]
Short-term borrowings											₩ 1,000,000		₩ 400,000
Debt instrument maturity date											Jul. 10, 2017
Debt instrument, rate of interest												12.00%	12.00%
Short Term Borrowings Four [Member] \| Woori Bank [Member]
Short-term borrowings										₩ 1,000,000		₩ 1,000,000	₩ 1,000,000
Debt instrument maturity date										Jun. 01, 2018
Debt instrument, rate of interest												4.27%	4.16%
Short Term Borrowings Five [Member] \| Woori Bank [Member]
Short-term borrowings							₩ 80,000					₩ 80,000	₩ 80,000
Debt instrument maturity date							Sep. 10, 2017
Debt instrument, rate of interest												14.00%	10.79%
Debt collateralized in savings account												₩ 4,000
Short Term Borrowings Six [Member] \| Woori Bank [Member]
Debt instrument, rate of interest												14.00%	10.24%
Debt collateralized in savings account												₩ 5,000
Bank overdraft												57,886	₩ 132,725
Short Term Borrowings Seven [Member] \| Suhyup Bank [Member]
Short-term borrowings						₩ 500,000						₩ 464,000	₩ 500,000
Debt instrument maturity date						Jul. 18, 2018
Debt instrument, rate of interest												2.50%	2.50%
Debt collateralized in savings account												₩ 3,000
Short Term Borrowings Eight [Member] \| Hana Bank [Member]
Short-term borrowings			₩ 300,000									₩ 300,000
Debt instrument maturity date			Aug. 01, 2018
Debt instrument, rate of interest												256.00%
Debt collateralized in savings account												₩ 300,000
Short Term Borrowings Nine [Member] \| GMT Co., Ltd. [Member]
Short-term borrowings				₩ 550,000								₩ 200,000
Debt instrument maturity date				Nov. 30, 2017
Debt instrument, rate of interest												600.00%
Short Term Borrowings Ten [Member] \| GNC Co., Ltd. [Member]
Short-term borrowings					₩ 300,000							₩ 300,000
Debt instrument maturity date					Nov. 30, 2017
Debt instrument, rate of interest												600.00%