INCOME TAXES - Schedule of Components of Income Tax Expense (Benefit) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Current:
U.S. Federal	$ (1.9)	$ 2.2	$ 8.9
U.S. State	1.9	(0.2)	7.0
Non-U.S.	0.1	0.2	(0.1)
Current income tax expense (benefit)	0.1	2.2	15.8
Deferred:
U.S. Federal	9.6	14.2	(0.6)
U.S. State	0.6	(0.2)	(3.5)
Non-U.S.	2.0	0.6	0.7
Deferred income tax expense (benefit)	12.2	14.6	(3.4)
Income tax expense	$ 12.3	$ 16.8	$ 12.4