FAIR VALUE MEASUREMENT - Summary of changes in the fair value of the company's Level 3 financial liabilities (Details) - Level 3 - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2021
Changes in fair value of level 3 financial liabilities
Balance at the beginning of the period	$ 32.1	$ 32.7
Settlements	(5.7)	(6.5)
Foreign Currency Translation	0.2	0.4
Balance at the end of the period	26.6	26.6
Contingent consideration liabilities
Changes in fair value of level 3 financial liabilities
Balance at the beginning of the period	32.1	32.7
Settlements	(5.7)	(6.5)
Foreign Currency Translation	0.2	0.4
Balance at the end of the period	$ 26.6	$ 26.6

Amount of foreign currency translation gain (loss) recognized in income from liability measured at fair value on recurring basis using unobservable input (level 3).

No definition available.

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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.

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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

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

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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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