RESTRUCTURING AND OTHER COSTS - RESTRUCTURING ACCURALS (Details) $ in Millions	3 Months Ended
	Mar. 31, 2018 USD ($)
Restructuring Reserve [Roll Forward]
Beginning Balance	$ 60.1
Provisions	7.6
Amounts applied	(11.6)
Change in estimates	(0.2)
Ending Balance	55.9
Severance
Restructuring Reserve [Roll Forward]
Beginning Balance	55.9
Provisions	7.0
Amounts applied	(10.8)
Change in estimates	(0.2)
Ending Balance	51.9
Severance | 2016 and Prior Plans
Restructuring Reserve [Roll Forward]
Beginning Balance	7.7
Provisions	0.2
Amounts applied	(1.5)
Change in estimates	0.0
Ending Balance	6.4
Severance | 2017 Plans
Restructuring Reserve [Roll Forward]
Beginning Balance	48.2
Provisions	(1.6)
Amounts applied	(4.2)
Change in estimates	(0.2)
Ending Balance	42.2
Severance | 2018 Plans
Restructuring Reserve [Roll Forward]
Beginning Balance	0.0
Provisions	8.4
Amounts applied	(5.1)
Change in estimates	0.0
Ending Balance	3.3
Lease/Contract Terminations
Restructuring Reserve [Roll Forward]
Beginning Balance	0.5
Provisions	0.2
Amounts applied	(0.5)
Ending Balance	0.2
Lease/Contract Terminations | 2016 and Prior Plans
Restructuring Reserve [Roll Forward]
Beginning Balance	0.3
Provisions	0.1
Amounts applied	(0.4)
Ending Balance	0.0
Lease/Contract Terminations | 2017 Plans
Restructuring Reserve [Roll Forward]
Beginning Balance	0.2
Provisions	0.0
Amounts applied	0.0
Ending Balance	0.2
Lease/Contract Terminations | 2018 Plans
Restructuring Reserve [Roll Forward]
Beginning Balance	0.0
Provisions	0.1
Amounts applied	(0.1)
Ending Balance	0.0
Other Restructuring Costs
Restructuring Reserve [Roll Forward]
Beginning Balance	3.7
Provisions	0.4
Amounts applied	(0.3)
Ending Balance	3.8
Other Restructuring Costs | 2016 and Prior Plans
Restructuring Reserve [Roll Forward]
Beginning Balance	2.0
Provisions	0.0
Amounts applied	(0.1)
Ending Balance	1.9
Other Restructuring Costs | 2017 Plans
Restructuring Reserve [Roll Forward]
Beginning Balance	1.7
Provisions	0.3
Amounts applied	(0.1)
Ending Balance	1.9
Other Restructuring Costs | 2018 Plans
Restructuring Reserve [Roll Forward]
Beginning Balance	0.0
Provisions	0.1
Amounts applied	(0.1)
Ending Balance	$ 0.0