EMPLOYEE BENEFIT PLANS - Components of Net Periodic Benefit Cost (Details) - USD ($) $ in Millions	12 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2019
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 19.4	$ 34.2	$ 34.5
Interest cost	10.2	11.4	15.6
Expected return on plan assets	(6.3)	(8.4)	(8.2)
Amortization of prior service (credit) cost	(3.6)	(6.7)	(5.7)
Amortization of net (gain) loss	1.2	0.5	(0.5)
Settlements (gain) loss recognized	3.8	(0.2)	(0.8)
Curtailment (gain) loss recognized	(6.9)	(14.9)	(5.4)
Net periodic benefit cost	17.8	15.9	29.5
Other Post-Employment Benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost	1.0	1.1	1.2
Interest cost	1.3	1.7	2.1
Expected return on plan assets	0.0	0.0	0.0
Amortization of prior service (credit) cost	(3.3)	(5.9)	(5.9)
Amortization of net (gain) loss	(0.1)	(0.1)	(0.1)
Settlements (gain) loss recognized	0.0	0.0	0.0
Curtailment (gain) loss recognized	0.0	(0.8)	0.0
Net periodic benefit cost	(1.1)	(4.0)	(2.7)
United States | Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Service cost	0.0	0.0	0.0
Interest cost	0.5	0.6	0.7
Expected return on plan assets	0.0	0.0	0.0
Amortization of prior service (credit) cost	0.0	0.0	0.0
Amortization of net (gain) loss	1.5	0.7	(0.7)
Settlements (gain) loss recognized	0.0	0.0	0.0
Curtailment (gain) loss recognized	0.0	0.0	0.0
Net periodic benefit cost	2.0	1.3	0.0
International | Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Service cost	18.4	33.1	33.3
Interest cost	8.4	9.1	12.8
Expected return on plan assets	(6.3)	(8.4)	(8.2)
Amortization of prior service (credit) cost	(0.3)	(0.8)	0.2
Amortization of net (gain) loss	(0.2)	(0.1)	0.3
Settlements (gain) loss recognized	3.8	(0.2)	(0.8)
Curtailment (gain) loss recognized	(6.9)	(14.1)	(5.4)
Net periodic benefit cost	$ 16.9	$ 18.6	$ 32.2