RESTRUCTURING AND OTHER COSTS - RESTRUCTURING ACCURALS (Details) $ in Millions	6 Months Ended
	Jun. 30, 2018 USD ($)
Restructuring Reserve [Roll Forward]
Beginning Balance	$ 60.3
Provisions	12.7
Amounts applied	(18.1)
Change in estimates	(2.1)
Ending Balance	52.8
Severance
Restructuring Reserve [Roll Forward]
Beginning Balance	55.9
Provisions	11.7
Amounts applied	(15.4)
Change in estimates	(2.1)
Ending Balance	50.1
Severance | 2016 and Prior Plans
Restructuring Reserve [Roll Forward]
Beginning Balance	7.7
Provisions	0.7
Amounts applied	(1.8)
Change in estimates	(0.1)
Ending Balance	6.5
Severance | 2017 Plans
Restructuring Reserve [Roll Forward]
Beginning Balance	48.2
Provisions	0.2
Amounts applied	(7.7)
Change in estimates	(1.8)
Ending Balance	38.9
Severance | 2018 Plans
Restructuring Reserve [Roll Forward]
Beginning Balance	0.0
Provisions	10.8
Amounts applied	(5.9)
Change in estimates	(0.2)
Ending Balance	4.7
Lease/Contract Terminations
Restructuring Reserve [Roll Forward]
Beginning Balance	0.6
Provisions	0.2
Amounts applied	(0.6)
Ending Balance	0.2
Lease/Contract Terminations | 2016 and Prior Plans
Restructuring Reserve [Roll Forward]
Beginning Balance	0.4
Provisions	0.3
Amounts applied	(0.5)
Ending Balance	0.2
Lease/Contract Terminations | 2017 Plans
Restructuring Reserve [Roll Forward]
Beginning Balance	0.2
Provisions	(0.1)
Amounts applied	(0.1)
Ending Balance	0.0
Other Restructuring Costs
Restructuring Reserve [Roll Forward]
Beginning Balance	3.8
Provisions	0.8
Amounts applied	(2.1)
Ending Balance	2.5
Other Restructuring Costs | 2016 and Prior Plans
Restructuring Reserve [Roll Forward]
Beginning Balance	2.1
Provisions	0.2
Amounts applied	(1.5)
Ending Balance	0.8
Other Restructuring Costs | 2017 Plans
Restructuring Reserve [Roll Forward]
Beginning Balance	1.7
Provisions	0.4
Amounts applied	(0.4)
Ending Balance	1.7
Other Restructuring Costs | 2018 Plans
Restructuring Reserve [Roll Forward]
Beginning Balance	0.0
Provisions	0.2
Amounts applied	(0.2)
Ending Balance	$ 0.0