Property and Equipment - Schedule of Components of Lease Property (Details) - KRW (₩) ₩ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment [Abstract]
Right-of-use lease assets - operating	₩ 450,933
Less: Accumulated depreciation	(184,152)
Right-of-use lease assets - operating, net	₩ 266,781

Amount of lessee's right to use underlying asset under operating lease.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977

Name:	us-gaap_OperatingLeaseRightOfUseAsset
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant