ACCUMULATED OTHER COMPREHENSIVE LOSS Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2018	Mar. 31, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018	Dec. 31, 2017
Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax	$ (130.5)	$ (131.0)	$ 135.4	$ 136.5	$ (130.5)	$ 135.4	$ (131.6)	$ (137.6)
Accumulated Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Net of Tax	(241.0)	(246.3)	(231.2)	(184.1)	(241.0)	(231.2)	(243.9)	(210.6)
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax	0.5	0.6	1.1	1.1	1.1	2.2
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Gain (Loss) Arising During Period, Net of Tax	5.3	(2.4)	(47.1)	26.5
Other Comprehensive Income (Loss), Net of Tax	5.8	(1.8)	(46.0)	27.6	4.0	(18.4)
Total accumulated other comprehensive loss	$ (371.5)	$ (377.3)	$ (366.6)	$ (320.6)	$ (371.5)	$ (366.6)	$ (375.5)	$ (348.2)

Amount, after tax, of accumulated other comprehensive (income) loss for defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

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Accumulated adjustment, net of tax, that results from the process of translating subsidiary financial statements and foreign equity investments into the reporting currency from the functional currency of the reporting entity, net of reclassification of realized foreign currency translation gains or losses.

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Amount after tax, before reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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