Consolidated Balance Sheets (Parenthetical) ₩ in Thousands	Dec. 31, 2017 KRW (₩) shares	Dec. 31, 2016 KRW (₩) shares
Statement of Financial Position [Abstract]
Accounts receivable, net of allowance for doubtful accounts | ₩	₩ 11,226,700	₩ 5,830,000
Common stock, shares authorized	100,000,000	300,000,000
Common stock, shares, issued	22,061,317	245,286
Common stock, shares, outstanding	22,061,317	245,286