FAIR VALUE MEASUREMENTS - NARRATIVE (Details) - USD ($)	Sep. 30, 2020	Dec. 31, 2019
Fair Value Disclosures [Abstract]
Period for contractual maturities of the Company's available-for-sale securities	1 year	1 year
Short-term investments	$ 0	$ 3,019,000

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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant