RESTRUCTURING AND OTHER COSTS - RESTRUCTURING ACCURALS (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Restructuring Reserve [Roll Forward]
Restructuring and other costs	$ 42.5	$ 20.5
Severance
Restructuring Reserve [Roll Forward]
Beginning Balance	27.0
Restructuring and other costs	2.3
Amounts applied	(3.8)
Change in estimates	(0.3)
Ending Balance	25.2
Severance | 2018 and Prior Plans
Restructuring Reserve [Roll Forward]
Beginning Balance	7.2
Restructuring and other costs	0.2
Amounts applied	(0.8)
Change in estimates	(0.1)
Ending Balance	6.5
Severance | 2019 Plans
Restructuring Reserve [Roll Forward]
Beginning Balance	19.8
Restructuring and other costs	0.7
Amounts applied	(3.0)
Change in estimates	(0.2)
Ending Balance	17.3
Severance | 2020 Plans
Restructuring Reserve [Roll Forward]
Beginning Balance	0.0
Restructuring and other costs	1.4
Amounts applied	0.0
Change in estimates	0.0
Ending Balance	1.4
Lease/Contract Terminations
Restructuring Reserve [Roll Forward]
Beginning Balance	0.5
Restructuring and other costs	0.1
Amounts applied	(0.1)
Ending Balance	0.5
Lease/Contract Terminations | 2018 and Prior Plans
Restructuring Reserve [Roll Forward]
Beginning Balance	0.5
Restructuring and other costs	0.1
Amounts applied	(0.1)
Ending Balance	0.5
Other Restructuring Costs
Restructuring Reserve [Roll Forward]
Beginning Balance	2.5
Restructuring and other costs	0.3
Amounts applied	(0.3)
Change in estimates	(0.1)
Ending Balance	2.4
Other Restructuring Costs | 2018 and Prior Plans
Restructuring Reserve [Roll Forward]
Beginning Balance	2.2
Restructuring and other costs	0.0
Amounts applied	0.0
Change in estimates	0.0
Ending Balance	2.2
Other Restructuring Costs | 2019 Plans
Restructuring Reserve [Roll Forward]
Beginning Balance	0.3
Restructuring and other costs	0.3
Amounts applied	(0.3)
Change in estimates	(0.1)
Ending Balance	$ 0.2