EMPLOYEE BENEFIT PLANS - Fair value of Plan Assets (Details) - USD ($) $ in Millions	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2016
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension assets	$ 262.2	$ 234.6	$ 95.6
Insurance contracts and other | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension assets	143.7	130.2	$ 42.4
Recurring
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension assets	262.2	234.6
Recurring | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension assets	118.5	104.4
Recurring | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension assets	0.0	0.0
Recurring | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension assets	143.7	130.2
Recurring | Equity securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension assets	63.0	53.4
Recurring | Equity securities | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension assets	63.0	53.4
Recurring | Equity securities | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension assets	0.0	0.0
Recurring | Equity securities | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension assets	0.0	0.0
Recurring | Corporate securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension assets	54.6	50.5
Recurring | Corporate securities | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension assets	54.6	50.5
Recurring | Corporate securities | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension assets	0.0	0.0
Recurring | Corporate securities | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension assets	0.0	0.0
Recurring | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension assets	0.9	0.5
Recurring | Cash and cash equivalents | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension assets	0.9	0.5
Recurring | Cash and cash equivalents | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension assets	0.0	0.0
Recurring | Cash and cash equivalents | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension assets	0.0	0.0
Recurring | Insurance contracts and other
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension assets	143.7	130.2
Recurring | Insurance contracts and other | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension assets	0.0	0.0
Recurring | Insurance contracts and other | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension assets	0.0	0.0
Recurring | Insurance contracts and other | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension assets	$ 143.7	$ 130.2