SHARE-BASED COMPENSATION PLANS - Schedule of Share-based Compensation (Details) - USD ($) $ in Millions	3 Months Ended						9 Months Ended
	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Mar. 31, 2021	Mar. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	$ 6.7			$ 18.8			$ 27.3	$ 32.8
Share-based compensation expense	6.0	$ 14.4	$ 6.2	3.5	$ 10.3	$ 6.2
Additional Paid-in Capital
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	6.0	$ 14.4	$ 6.2	3.5	$ 10.3	$ 6.2
Equity plan expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	6.0			1.6			24.6	14.6
Equity plan expense | Additional Paid-in Capital
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	6.0			3.5			26.6	20.0
Equity plan expense | Additional Paid-in Capital | Discontinued Operations
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	0.0			1.9			2.0	5.4
Equity plan modified and cash settled
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	0.0			19.0			0.9	19.0
Liability plan (income) expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	0.7			(1.9)			1.4	(1.9)
Fringe expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	$ 0.0			$ 0.1			$ 0.4	$ 1.1