INVESTMENTS (Details) $ in Thousands	6 Months Ended
Jun. 30, 2020 USD ($)
Investments by security type
Amortized Cost	$ 56,553
Gross Unrealized Losses	(17)
Fair Value	56,536
U.S. treasury securities
Investments by security type
Amortized Cost	27,980
Gross Unrealized Losses	(8)
Fair Value	27,972
U.S. government agencies securities
Investments by security type
Amortized Cost	28,573
Gross Unrealized Losses	(9)
Fair Value	$ 28,564

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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