FAIR VALUE MEASUREMENTS - Fair Value of Contingent Consideration (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020
Fair Value Disclosures [Abstract]
Beginning balance	$ 2,477
Purchase price contingent consideration	350,348	$ 0
Changes in fair value	9,201	$ 0
Payments	(164)
Ending balance	$ 361,862

Business Combination, Contingent Consideration Arrangements, Increase Due to Acquisition

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- Definition

Business Combination, Contingent Consideration, Gain (Loss), Change in Fair Value

+ References

No definition available.

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- Definition

Amount of liability recognized arising from contingent consideration in a business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=120321790&loc=d3e6927-128479

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-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

Reference 3: 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

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Amount of cash outflow, made soon after acquisition date of business combination, to settle contingent consideration liability.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3213-108585

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