EMPLOYEE BENEFIT PLANS - Pre-tax Amounts Recognized in AOCI (Details) - USD ($) $ in Millions	Jun. 30, 2020	Jun. 30, 2019
Defined Benefit Plan Disclosure [Line Items]
Net actuarial (loss) gain	$ 0.7	$ (29.2)
Prior service credit (cost)	8.0	19.1
Total recognized in AOC(L)/I	8.7	(10.1)
Other Post-Employment Benefits
Defined Benefit Plan Disclosure [Line Items]
Net actuarial (loss) gain	4.2	(0.4)
Prior service credit (cost)	4.1	10.4
Total recognized in AOC(L)/I	8.3	10.0
United States | Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Net actuarial (loss) gain	(0.7)	0.2
Prior service credit (cost)	0.0	0.0
Total recognized in AOC(L)/I	(0.7)	0.2
International | Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Net actuarial (loss) gain	(2.8)	(29.0)
Prior service credit (cost)	3.9	8.7
Total recognized in AOC(L)/I	$ 1.1	$ (20.3)