FAIR VALUE MEASUREMENT AND FINANCIAL INSTRUMENTS - Additional Information (Details) $ in Thousands	6 Months Ended
Jun. 30, 2020 USD ($)	Dec. 31, 2019
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Contingent consideration liability measurements used	0.145	0.118
Royalty rate	2.00%
Significant Unobservable Inputs (Level 3)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Change in fair value of contingent consideration	$ (35,220)
Discount Rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Weighted-average cost of capital	13.20%	5.60%

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- Definition

Value of input used to measure contingent consideration liability from business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Amount of increase (decrease) of financial instrument classified as a derivative asset (liability) after deduction of derivative liability (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 3
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