ACCUMULATED OTHER COMPREHENSIVE LOSS - Reclassification out of Accumulated Comprehensive Loss (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	$ (614.8)
Ending balance	(642.0)
Interest rate swap
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Ending balance	(2.4)
Deferred gain - hedging
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	(3.0)
Ending balance	(2.4)
Deferred gain - hedging | Interest rate swap
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	(3.0)	$ (3.8)
Ending balance	(2.4)	(4.7)
Deferred gain - hedging | Interest rate swap | Reclassification out of Accumulated Other Comprehensive Income (Loss) [Member]
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Change in fair value, net of tax		(1.6)
Other Comprehensive Income (Loss), Tax [Abstract]
Change in fair value - tax expense (benefit)	0.0
Deferred gain - hedging | Interest rate swap | Interest Expense | Reclassification out of Accumulated Other Comprehensive Income (Loss) [Member]
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Reclassifications into earnings, net of tax	0.6	0.7
Other Comprehensive Income (Loss), Tax [Abstract]
Reclassifications into earnings - tax expense (benefit)	$ 0.4	$ (0.4)