Income Taxes - Schedule of Provision for Income Tax (Details) (10 K) - KRW (₩) ₩ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Current
Deferred			16,850	(9,118)
Total	₩ (1,621)	₩ (2,930)	₩ 16,850	₩ (9,118)

Amount of deferred income tax expense (benefit) pertaining to income (loss) from continuing operations.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration