EMPLOYEE BENEFIT PLANS - Fair value of Plan Assets (Details) - USD ($) $ in Millions	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2015
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension assets	$ 234.6	$ 95.6	$ 88.8
Insurance contracts and Other | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension assets	130.2	42.4	$ 36.6
Recurring
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension assets	234.6	95.9
Recurring | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension assets	104.4	10.3
Recurring | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension assets	0.0	43.2
Recurring | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension assets	130.2	42.4
Recurring | International equity securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension assets	53.4	0.0
Recurring | International equity securities | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension assets	53.4	0.0
Recurring | International equity securities | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension assets	0.0	0.0
Recurring | International equity securities | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension assets	0.0	0.0
Recurring | U.S. Government and government agencies
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension assets	0.0	18.9
Recurring | U.S. Government and government agencies | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension assets	0.0	5.8
Recurring | U.S. Government and government agencies | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension assets	0.0	13.1
Recurring | U.S. Government and government agencies | 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	50.5	6.8
Recurring | Corporate securities | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension assets	50.5	0.0
Recurring | Corporate securities | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension assets	0.0	6.8
Recurring | Corporate securities | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension assets	0.0	0.0
Recurring | Commingled bond fund
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension assets	0.0	23.3
Recurring | Commingled bond fund | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension assets	0.0	0.0
Recurring | Commingled bond fund | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension assets	0.0	23.3
Recurring | Commingled bond fund | 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	0.5	4.5
Recurring | Cash and cash equivalents | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension assets	0.5	4.5
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	130.2	42.4
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	$ 130.2	$ 42.4