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FAIR VALUE MEASUREMENTS - SCHEDULE OF SHORT-TERM INVESTMENTS (Details) - USD ($)
Jun. 30, 2020
Dec. 31, 2019
Debt Securities, Available-for-sale [Line Items]    
Amortized Cost   $ 3,018,000
Gross Unrealized Holding Gains   1,000
Gross Unrealized Holding Losses   0
Fair Value $ 0 3,019,000
U.S. Treasury securities    
Debt Securities, Available-for-sale [Line Items]    
Amortized Cost   3,018,000
Gross Unrealized Holding Gains   1,000
Gross Unrealized Holding Losses   0
Fair Value   $ 3,019,000