ACCUMULATED OTHER COMPREHENSIVE LOSS - Reclassification out of Accumulated Comprehensive Loss (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	[1]			$ (587.5)
Ending balance		$ (561.7)		(561.7)
Other Comprehensive Income (Loss), Tax [Abstract]
Reclassifications into earnings - tax expense (benefit)		0.4	$ 0.2	0.8	$ 0.2
Change in fair value - tax expense (benefit)		(0.3)	(0.2)	(1.2)	(1.4)
Deferred Gain (Loss) - Hedging [Member]
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance				(3.8)
Ending balance		(4.5)		(4.5)
Deferred Gain (Loss) - Hedging [Member] | Interest Rate Swap [Member]
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance		(4.7)	(4.1)	(3.8)	(2.2)
Ending balance		(4.5)	(4.2)	(4.5)	(4.2)
Deferred Gain (Loss) - Hedging [Member] | Interest Rate Swap [Member] | Interest Expense [Member] | 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		0.7	0.3	1.3	0.3
Change in fair value, net of tax		$ (0.5)	$ (0.4)	$ (2.0)	$ (2.3)

[1] Adjusted as a result of the adoption of certain accounting pronouncements beginning on January 1, 2016. See Note 1, "Description of Business and Summary of Significant Accounting Policies - Recently Adopted Accounting Pronouncements" for details of these adjustments.