FAIR VALUE MEASUREMENTS - Summary of changes in the fair value of the company's Level 3 financial liabilities (Details) $ in Millions	6 Months Ended
Jun. 30, 2019 USD ($)
Changes in fair value of level 3 financial liabilities
Balance at the beginning of the period	$ 3.9
Realized (gains) losses during period	1.6
Balance at the end of the period	5.5
Contingent consideration liability to related party
Changes in fair value of level 3 financial liabilities
Balance at the beginning of the period	3.9
Realized (gains) losses during period	1.6
Balance at the end of the period	$ 5.5

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

+ Details

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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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