ACCUMULATED OTHER COMPREHENSIVE LOSS - Reclassification out of Accumulated Comprehensive Loss (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2018
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	$ (855.7)	$ (770.4)
Ending balance	(980.7)	(980.7)
Interest rate swap \| Deferred gain - hedging
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	(0.1)	(0.7)
Reclassifications into earnings, net of tax	0.1	0.7
Ending balance	0.0	0.0
Reclassifications into earnings, tax benefit	$ 0.3	$ 0.5

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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Amount after tax of reclassification adjustments of other comprehensive income (loss) attributable to parent.

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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income (loss).

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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