RESTRUCTURING COSTS - Restructuring Costs by Program (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended		12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2017
Restructuring Cost and Reserve [Line Items]
Restructuring costs	$ 134.9	$ 21.5	$ 140.9	$ 37.0
Turnaround Plan
Restructuring Cost and Reserve [Line Items]
Restructuring costs	137.9	0.0	146.6	0.0
Global Integration Activities
Restructuring Cost and Reserve [Line Items]
Restructuring costs	(2.7)	22.2	(4.4)	28.7	$ 28.5	$ 106.5	$ 365.0
2018 Restructuring Actions
Restructuring Cost and Reserve [Line Items]
Restructuring costs	(0.2)	(0.3)	(1.0)	8.8
Other Restructuring
Restructuring Cost and Reserve [Line Items]
Restructuring costs	$ (0.1)	$ (0.4)	$ (0.3)	$ (0.5)