DERIVATIVE INSTRUMENTS - Gains and Losses Recognized in OCI (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2019
Derivative [Line Items]
Gain (Loss) Recognized in OCI	$ (174.4)	$ (99.3)	$ (347.5)	$ 58.0
Foreign exchange forward contracts
Derivative [Line Items]
Gain (Loss) Recognized in OCI	0.8	(1.0)	(0.4)	(0.6)
Interest rate swap contracts
Derivative [Line Items]
Gain (Loss) Recognized in OCI	0.2	4.1	0.4	3.6
Cross-currency swap contracts
Derivative [Line Items]
Gain (Loss) Recognized in OCI	$ 0.0	$ (22.6)	$ (25.1)	$ (18.7)