FAIR VALUE MEASUREMENTS - Changes in fair value, Level 3 (Details) $ in Thousands	6 Months Ended
Jun. 30, 2020 USD ($)
FAIR VALUE MEASUREMENTS AND SHORT-TERM INVESTMENTS
Fair value at beginning of the period	$ 11,128
Unrealized loss as a result of change in fair value	(133)
Accretion of interest on Panacea investment	306
Fair value at end of the period	$ 11,301

Amount of unrealized gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3) and still held.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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- References

No definition available.

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- Definition

Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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- Definition

Represents accreted interest income on convertible note receivable.

+ References

No definition available.

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