SHARE-BASED COMPENSATION PLANS - Share-based Compensation Expense (Details) - USD ($) $ in Millions	12 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	$ 42.2	$ 11.7	$ 30.4
Share-based compensation expense	31.8	16.9	31.5
Additional Paid-in Capital
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	31.8	16.9	31.5
Additional Paid-in Capital | Discontinued Operations
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	7.0
Equity plan expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	24.8	13.4	28.9
Equity plan modified and cash settled
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	18.3	0.0	0.0
Liability plan (income) expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	(2.0)	(2.1)	(1.0)
Fringe expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	$ 1.1	$ 0.4	$ 2.5