SHARE-BASED COMPENSATION PLANS - Share-based Compensation Expense (Details) - USD ($) $ in Millions	12 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	$ 28.4	$ 42.2	$ 11.7
Share-based compensation expense	27.4	31.8	16.9
Additional Paid-in Capital
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	27.4	31.8	16.9
Additional Paid-in Capital | Discontinued Operations
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	2.0	7.0
Equity plan expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	25.4	24.8	13.4
Equity plan modified and cash settled
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	0.9	18.3	0.0
Liability plan (income) expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	1.6	(2.0)	(2.1)
Fringe expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	$ 0.5	$ 1.1	$ 0.4