GOODWILL AND INTANGIBLE ASSETS, NET - Schedule of Purchased Intangible Assets (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Acquired Finite-Lived Intangible Assets [Line Items]
Gross	$ 190.6	$ 190.6
Accumulated Amortization	(99.4)	(75.2)
Net	$ 91.2	$ 115.4
Weighted Average Remaining Life (in Years)	9 years 4 months 24 days	9 years 9 months 18 days
Intangible assets, gross	$ 191.8	$ 191.8
Accumulated Amortization	(99.4)	(75.2)
Intangible assets, net	92.4	116.6
Land rights
Acquired Indefinite-lived Intangible Assets [Line Items]
Indefinite-lived intangible assets	1.2	1.2
Customer relationships
Acquired Finite-Lived Intangible Assets [Line Items]
Gross	108.5	108.5
Accumulated Amortization	(59.7)	(43.1)
Net	$ 48.8	$ 65.4
Weighted Average Remaining Life (in Years)	3 years 10 months 24 days	4 years 8 months 12 days
Accumulated Amortization	$ (59.7)	$ (43.1)
Trade names
Acquired Finite-Lived Intangible Assets [Line Items]
Gross	44.5	44.5
Accumulated Amortization	(13.6)	(11.1)
Net	$ 30.9	$ 33.4
Weighted Average Remaining Life (in Years)	19 years 1 month 6 days	19 years 7 months 6 days
Accumulated Amortization	$ (13.6)	$ (11.1)
Non-competes
Acquired Finite-Lived Intangible Assets [Line Items]
Gross	18.3	18.3
Accumulated Amortization	(15.3)	(12.1)
Net	$ 3.0	$ 6.2
Weighted Average Remaining Life (in Years)	2 years 4 months 24 days	2 years 7 months 6 days
Accumulated Amortization	$ (15.3)	$ (12.1)
Leasehold interests
Acquired Finite-Lived Intangible Assets [Line Items]
Gross	12.5	12.5
Accumulated Amortization	(6.7)	(5.1)
Net	$ 5.8	$ 7.4
Weighted Average Remaining Life (in Years)	5 years 4 months 24 days	5 years 10 months 24 days
Accumulated Amortization	$ (6.7)	$ (5.1)
Favorable contract
Acquired Finite-Lived Intangible Assets [Line Items]
Gross	4.0	4.0
Accumulated Amortization	(3.9)	(3.8)
Net	$ 0.1	$ 0.2
Weighted Average Remaining Life (in Years)	10 months 24 days	1 year 10 months 24 days
Accumulated Amortization	$ (3.9)	$ (3.8)
Environmental credits
Acquired Finite-Lived Intangible Assets [Line Items]
Gross	2.8	2.8
Accumulated Amortization	(0.2)	0.0
Net	$ 2.6	$ 2.8
Weighted Average Remaining Life (in Years)	16 years	17 years
Accumulated Amortization	$ (0.2)	$ 0.0