FAIR VALUE MEASUREMENT AND FINANCIAL INSTRUMENTS - Summary of Changes in Fair Value of Contingent Consideration (Details) $ in Thousands	3 Months Ended
Mar. 31, 2021 USD ($)
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Change in fair value of contingent consideration - short term	$ 850
Change in fair value of contingent consideration - long term	47,310
Unobservable Inputs (Level 3)
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Ending balance	$ 157,000

Business Combination, Contingent Consideration Arrangements, Change in Amount of Contingent Consideration, Liability, Current

No definition available.

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- Definition

Business Combination, Contingent Consideration Arrangements, Change in Amount of Contingent Consideration, Liability, Noncurrent

+ References

No definition available.

+ Details

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- Definition

Amount of liability recognized arising from contingent consideration in a business combination, expected to be settled beyond one year or the normal operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 25
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=6911189&loc=d3e6408-128476

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 35
-Paragraph 1
-Subparagraph b
-URI http://asc.fasb.org/extlink&oid=116859824&loc=d3e6819-128478

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

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