RESTRUCTURING CHARGES - Restructuring and Related Charges Activity (Details) $ in Millions	6 Months Ended
	Jun. 30, 2021 USD ($)
Total Restructuring Charges
Restructuring Reserve [Roll Forward]
Charges incurred during period	$ 13.8
RGGA Program
Restructuring Reserve [Roll Forward]
Charges incurred through beginning of period	68.8
Charges incurred during period	17.2
Charges incurred through end of period	86.0
RGGA Program | Total Restructuring Charges
Restructuring Reserve [Roll Forward]
Charges incurred through beginning of period	50.5
Charges incurred during period	13.8
Charges incurred through end of period	64.3
RGGA Program | Employee Severance and Other Personnel Benefits
Restructuring Reserve [Roll Forward]
Charges incurred through beginning of period	48.6
Charges incurred during period	3.0
Charges incurred through end of period	51.6
RGGA Program | Other Costs
Restructuring Reserve [Roll Forward]
Charges incurred through beginning of period	1.9
Charges incurred during period	10.8
Charges incurred through end of period	12.7
RGGA Program | Leases
Restructuring Reserve [Roll Forward]
Charges incurred through beginning of period	12.6
Charges incurred during period	2.6
Charges incurred through end of period	15.2
RGGA Program | Other Related Charges
Restructuring Reserve [Roll Forward]
Charges incurred through beginning of period	5.7
Charges incurred during period	0.8
Charges incurred through end of period	$ 6.5