INCOME TAXES - Unrecognized Tax Benefits (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Beginning balance	$ 30.8	$ 31.8	$ 52.8
Additions for prior year tax positions	0.6	0.9	0.0
Reductions for expirations of statute of limitations	(0.9)	(1.9)	(1.5)
Reductions for prior year tax positions and reclassifications	(0.2)	0.0	(19.5)
Ending balance	$ 30.3	$ 30.8	$ 31.8