SHORT-TERM INVESTMENTS (Details) - USD ($) |
Jun. 30, 2019 |
Dec. 31, 2018 |
|---|---|---|
| SHORT-TERM INVESTMENTS | ||
| Debt securities, available-for-sale | $ 19,903,000 | $ 66,218,000 |
| X | ||||||||||
- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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| X | ||||||||||
- References No definition available.
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