LEASES - Lease Cost (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Leases [Abstract]
Operating lease expense	$ 23.8	$ 28.6
Finance lease expense:
Amortization of right of use assets	0.5	0.6
Interest on lease liabilities	1.3	1.1
Total finance lease expense	1.8	1.7
Short-term lease expense	5.0	6.2
Variable lease expense	5.6	7.7
Total lease expense	36.2	44.2
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	21.7	34.0
Operating cash flows from finance leases	1.3	1.1
Financing cash flows from finance leases	2.1	0.6
Right of use assets obtained in exchange for new operating lease liabilities	2.4	8.0
Right of use assets obtained in exchange for new finance lease liabilities	$ 1.0	$ 0.0
Weighted average remaining lease term (amounts in years)
Operating leases	6 years 3 months
Finance leases	22 years 9 months 25 days
Weighted average discount rate
Operating leases	5.60%
Finance leases	13.00%