SHORT TERM INVESTMENTS (Details)
6 Months Ended 12 Months Ended
Jun. 30, 2019
Dec. 31, 2018
Cash and Cash Equivalents [Line Items]    
Maturity of Time Deposits 4 months 4 months
Minimum [Member]    
Cash and Cash Equivalents [Line Items]    
Percentage of Interest Bearing Bank Deposits 0.05% 0.05%
Maximum [Member]    
Cash and Cash Equivalents [Line Items]    
Percentage of Interest Bearing Bank Deposits 3.15% 3.15%