INCOME TAXES - Unrecognized Tax Benefits (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Unrecognized Tax Benefit, Tax Portion [Abstract]
Beginning Balance	$ 64.9	$ 75.9
Increase based on tax positions taken in a prior year	0.3	2.8
Decrease based on tax positions taken in a prior year	(2.2)	(15.5)
Increase based on tax positions taken in the current year	7.1	6.5
Decrease resulting from the lapse of statutes of limitations	(3.8)	(4.8)
Ending Balance	66.3	64.9
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued [Abstract]
Beginning Balance	9.8	9.0
Increase based on tax positions taken in a prior year	3.4	5.4
Decrease based on tax positions taken in a prior year	(0.3)	(3.8)
Increase based on tax positions taken in the current year	0.0	0.2
Decrease resulting from the lapse of statutes of limitations	(1.2)	(1.0)
Ending Balance	11.7	9.8
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Beginning balance	74.7	84.9
Increase based on tax positions taken in a prior year	3.7	8.2
Decrease based on tax positions taken in a prior year	(2.5)	(19.3)
Increase based on tax positions taken in the current year	7.1	6.7
Decrease resulting from the lapse of statutes of limitations	(5.0)	(5.8)
Ending balance	$ 78.0	$ 74.7