LEASES - Income and Expenses (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Leases [Abstract]
Operating lease cost	$ 16.0	$ 16.8
Amortization of right-of-use assets	0.3	0.4
Interest on lease liabilities	0.1	0.1
Short-term leases costs	0.4	1.1
Sublease income	(4.1)	(3.2)
Net lease cost	$ 12.7	$ 15.2