REDEEMABLE NONCONTROLLING INTERESTS (Changes In Redeemable Noncontrolling Interest) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Changes in redeemable noncontrolling interest [Roll Forward]
Balance as of january 1,	$ 1,004.8	$ 1,126.2	$ 1,091.3
Additions to redeemable noncontrolling interests		28.1
Net income attributable to noncontrolling interests	35.8	(87.9)	(33.4)
Adjustment to noncontrolling interest redemption value	(35.8)	86.7	0.0
Adjustment to noncontrolling interest due to merger	0.0	(28.1)	0.0
Purchase of redeemable noncontrolling interest	(425.7)	0.0	0.0
Foreign currency translation adjustment attributable to noncontrolling interests	(8.3)	(92.1)	68.3
Balance as of december 31,	1,096.5	$ 1,004.8	$ 1,126.2
MTN and Eure-et-Loir [Member]
Changes in redeemable noncontrolling interest [Roll Forward]
Additions to redeemable noncontrolling interests	$ 525.7

Noncontrolling interest, decrease due to merger

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

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Amount of increase in noncontrolling interest from a business combination.

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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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