RESTRUCTURING COSTS - Restructuring Costs (Details) - USD ($) $ in Millions	12 Months Ended			24 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2021
Restructuring Cost and Reserve [Line Items]
Restructuring costs	$ 63.6	$ 130.2	$ 34.2
Transformation Plan
Restructuring Cost and Reserve [Line Items]
Restructuring costs	73.2	156.6	0.0	$ 229.8
Transformation Plan | Severance and Employee Benefits
Restructuring Cost and Reserve [Line Items]
Restructuring costs	73.4	151.2		224.6
Transformation Plan | Fixed Asset Write-offs
Restructuring Cost and Reserve [Line Items]
Restructuring costs	(0.5)	(1.1)		(1.6)
Transformation Plan | Other Exit Costs
Restructuring Cost and Reserve [Line Items]
Restructuring costs	0.3	6.5		$ 6.8
Other Exit Costs
Restructuring Cost and Reserve [Line Items]
Restructuring costs	$ (9.6)	$ (26.4)	$ 34.2