FAIR VALUE MEASUREMENT - Summary of changes in the fair value of the company's Level 3 financial liabilities (Details) $ in Millions	3 Months Ended
Mar. 31, 2020 USD ($)
Changes in fair value of level 3 financial liabilities
Balance at the beginning of the period	$ 2.2
Additions	17.5
Settlements	(2.2)
Balance at the end of the period	17.5
Contingent consideration liabilities
Changes in fair value of level 3 financial liabilities
Balance at the beginning of the period	2.2
Additions	17.5
Settlements	(2.2)
Balance at the end of the period	$ 17.5

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

No definition available.

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- Definition

Amount of purchases of financial instrument classified as a liability 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)(2)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

+ Details

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- Definition

Amount of settlements of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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- Definition

Fair value of financial instrument classified as a liability 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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