EQUITY AND CONVERTIBLE PREFERRED STOCK - Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	12 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2018
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	$ 4,593.4	$ 8,855.2	$ 9,317.7
Total other comprehensive (loss) income, net of tax	(397.3)	(217.5)	148.4
Ending balance	3,228.8	4,593.4	8,855.2
Total
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	(58.8)	158.8	4.4
Other comprehensive income before reclassifications	(397.9)	(202.6)
Less: Net amounts reclassified from AOCI/(L)	0.5	(15.0)
Total other comprehensive (loss) income, net of tax	(397.4)	(217.6)	147.9
Ending balance	(456.2)	(58.8)	158.8
(Losses) Gains on Cash Flow Hedges
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	(13.3)	31.7
Other comprehensive income before reclassifications	(37.5)	(35.5)
Less: Net amounts reclassified from AOCI/(L)	7.8	(9.5)
Total other comprehensive (loss) income, net of tax	(29.7)	(45.0)
Ending balance	(43.0)	(13.3)	31.7
(Losses) Gains on Net Investment Hedge
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	214.8	115.0
Other comprehensive income before reclassifications	47.1	99.8
Less: Net amounts reclassified from AOCI/(L)	0.0	0.0
Total other comprehensive (loss) income, net of tax	47.1	99.8
Ending balance	261.9	214.8	115.0
Foreign Currency Translation Adjustments
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	(257.4)	(44.3)
Other comprehensive income before reclassifications	(426.4)	(213.1)
Less: Net amounts reclassified from AOCI/(L)	0.0	0.0
Total other comprehensive (loss) income, net of tax	(426.4)	(213.1)
Ending balance	(683.8)	(257.4)	(44.3)
Pension and Other Post-Employment Benefit Plans
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	(2.9)	56.4
Other comprehensive income before reclassifications	18.9	(53.8)
Less: Net amounts reclassified from AOCI/(L)	(7.3)	(5.5)
Total other comprehensive (loss) income, net of tax	11.6	(59.3)
Ending balance	8.7	(2.9)	$ 56.4
Amortization of actuarial losses
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Less: Net amounts reclassified from AOCI/(L)	10.5	7.0
Amortization of actuarial gains (losses), tax	$ 3.2	$ 1.5