REDEEMABLE NONCONTROLLING INTERESTS - CHANGE IN REDEEMABLE NONCONTROLLING INTEREST (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018
Increase (Decrease) in Temporary Equity [Roll Forward]
Balance as of January 1,	$ 1,004.8	$ 1,126.2
Net income (loss) attributable to noncontrolling interests	2.2	(42.4)
Adjustment to noncontrolling interest redemption value	(2.2)	28.6
Adjustment to noncontrolling interest due to merger	0.0	(20.5)
Purchase of redeemable noncontrolling interest	425.7	0.0
Foreign currency translation adjustment attributable to noncontrolling interests	(4.3)	(129.5)
Balance as of June 30,	574.8	954.8
Merger
Increase (Decrease) in Temporary Equity [Roll Forward]
Adjustment to noncontrolling interest due to merger	$ 0.0	$ (28.1)

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

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- Definition

Change in noncontrolling interest during the period as a result of a change in the redemption value of redeemable noncontrolling interest.

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- Definition

Decrease in noncontrolling interest (for example, but not limited to, redeeming or purchasing the interests of noncontrolling shareholders, issuance of shares (interests) by the non-wholly owned subsidiary to the parent entity for other than cash, and a buyback of shares (interest) by the non-wholly owned subsidiary from the noncontrolling interests).

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Amount of Net Income (Loss) attributable to redeemable noncontrolling interest.

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The cash outflow during the period for redemption of redeemable noncontrolling interests.

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As of the reporting date, the aggregate carrying amount of all noncontrolling interests which are redeemable by the (parent) entity (1) at a fixed or determinable price on a fixed or determinable date, (2) at the option of the holder of the noncontrolling interest, or (3) upon occurrence of an event that is not solely within the control of the (parent) entity. This item includes noncontrolling interest holder's ownership (or holders' ownership) regardless of the type of equity interest (common, preferred, other) including all potential organizational (legal) forms of the investee entity.

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Adjustments to temporary equity resulting from foreign currency translation adjustments.

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