RESTRUCTURING CHARGES - Restructuring Reserve (Details) $ in Millions	3 Months Ended
	Mar. 31, 2022 USD ($)
Total Restructuring Charges
Restructuring Reserve [Roll Forward]
Liability Balance at period start	$ 2.7
Expense, Net	1.9
Cash Utilized, Net	(1.9)
Liability Balance at period end	2.7
RGGA:
Restructuring Reserve [Roll Forward]
Expense, Net	4.0
RGGA: | Total Restructuring Charges
Restructuring Reserve [Roll Forward]
Liability Balance at period start	1.9
Expense, Net	1.9
Cash Utilized, Net	(1.9)
Liability Balance at period end	1.9
RGGA: | Employee severance and other personnel benefits
Restructuring Reserve [Roll Forward]
Liability Balance at period start	1.9
Expense, Net	0.5
Cash Utilized, Net	(0.5)
Liability Balance at period end	1.9
RGGA: | Other
Restructuring Reserve [Roll Forward]
Liability Balance at period start	0.0
Expense, Net	1.4
Cash Utilized, Net	(1.4)
Liability Balance at period end	0.0
Other restructuring initiatives: | Total Restructuring Charges
Restructuring Reserve [Roll Forward]
Liability Balance at period start	0.8
Expense, Net	0.0
Cash Utilized, Net	0.0
Liability Balance at period end	0.8
Other restructuring initiatives: | Employee severance and other personnel benefits
Restructuring Reserve [Roll Forward]
Liability Balance at period start	0.8
Expense, Net	0.0
Cash Utilized, Net	0.0
Liability Balance at period end	$ 0.8