RESTRUCTURING CHARGES - Restructuring Reserve (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Restructuring Reserve [Roll Forward]
Liability Balance at period start	$ 13.8	$ 10.0
Expense, Net	26.1	49.7
Foreign Currency Translation		0.2
Cash Utilized, Net	(37.2)	(46.1)
Liability Balance at period end	2.7	13.8
RGGA:
Restructuring Reserve [Roll Forward]
Expense, Net	33.1
RGGA: | Total Restructuring Charges
Restructuring Reserve [Roll Forward]
Liability Balance at period start	12.6	0.0
Expense, Net	26.1	50.5
Foreign Currency Translation		0.0
Cash Utilized, Net	(36.8)	(37.9)
Liability Balance at period end	1.9	12.6
RGGA: | Employee severance and other personnel benefits
Restructuring Reserve [Roll Forward]
Liability Balance at period start	12.6	0.0
Expense, Net	4.1	48.6
Foreign Currency Translation		0.0
Cash Utilized, Net	(14.8)	(36.0)
Liability Balance at period end	1.9	12.6
RGGA: | Other
Restructuring Reserve [Roll Forward]
Liability Balance at period start	0.0	0.0
Expense, Net	22.0	1.9
Foreign Currency Translation		0.0
Cash Utilized, Net	(22.0)	(1.9)
Liability Balance at period end	0.0	0.0
2018 Optimization Program: | Total Restructuring Charges
Restructuring Reserve [Roll Forward]
Liability Balance at period start	1.1	5.7
Expense, Net		(0.6)
Foreign Currency Translation		0.0
Cash Utilized, Net		(4.0)
Liability Balance at period end		1.1
2018 Optimization Program: | Employee severance and other personnel benefits
Restructuring Reserve [Roll Forward]
Liability Balance at period start	1.1	5.7
Expense, Net		(0.6)
Foreign Currency Translation		0.0
Cash Utilized, Net		(4.0)
Liability Balance at period end		1.1
Other restructuring initiatives: | Employee severance and other personnel benefits
Restructuring Reserve [Roll Forward]
Liability Balance at period start	1.2
Expense, Net	0.0
Cash Utilized, Net	(0.4)
Liability Balance at period end	0.8	1.2
Other restructuring initiatives: | Employee severance and other personnel benefits
Restructuring Reserve [Roll Forward]
Liability Balance at period start	$ 0.1	4.3
Expense, Net		(0.2)
Foreign Currency Translation		0.2
Cash Utilized, Net		(4.2)
Liability Balance at period end		$ 0.1