GOODWILL AND OTHER INTANGIBLE ASSETS, NET - Schedule of Goodwill (Details) - USD ($)	3 Months Ended	12 Months Ended
	Jun. 30, 2020	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2018
Goodwill [Roll Forward]
Gross beginning balance		$ 8,101,900,000	$ 8,223,200,000
Accumulated impairments	$ (4,040,100,000)	(4,040,100,000)	(3,935,100,000)	$ (627,600,000)
Net beginning balance		4,166,800,000	7,595,600,000
Acquisitions		128,600,000
Impairment charges	0	(105,000,000.0)	(3,307,500,000)	0
Measurement period adjustments			(9,700,000)
Foreign currency translation		(193,600,000)	(111,600,000)
Dispositions		(22,900,000)
Gross ending balance	8,014,000,000.0	8,014,000,000.0	8,101,900,000	8,223,200,000
Accumulated impairments	(4,040,100,000)	(4,040,100,000)	(3,935,100,000)	(627,600,000)
Net ending balance	3,973,900,000	3,973,900,000	4,166,800,000	7,595,600,000
Americas
Goodwill [Roll Forward]
Gross beginning balance		3,069,400,000	3,117,400,000
Accumulated impairments	(1,768,700,000)	(1,768,700,000)	(1,768,700,000)	(206,100,000)
Net beginning balance		1,300,700,000	2,911,300,000
Acquisitions		128,600,000
Impairment charges		0	(1,562,600,000)
Measurement period adjustments			(2,200,000)
Foreign currency translation		(75,000,000.0)	(45,800,000)
Dispositions		(10,800,000)
Gross ending balance	3,112,200,000	3,112,200,000	3,069,400,000	3,117,400,000
Accumulated impairments	(1,768,700,000)	(1,768,700,000)	(1,768,700,000)	(206,100,000)
Net ending balance	1,343,500,000	1,343,500,000	1,300,700,000	2,911,300,000
EMEA
Goodwill [Roll Forward]
Gross beginning balance		3,737,900,000	3,793,400,000
Accumulated impairments	(1,857,300,000)	(1,857,300,000)	(1,752,300,000)	(297,000,000.0)
Net beginning balance		1,985,600,000	3,496,400,000
Acquisitions		0
Impairment charges		(105,000,000.0)	(1,455,300,000)
Measurement period adjustments			(4,800,000)
Foreign currency translation		(88,900,000)	(50,700,000)
Dispositions		(10,100,000)
Gross ending balance	3,638,900,000	3,638,900,000	3,737,900,000	3,793,400,000
Accumulated impairments	(1,857,300,000)	(1,857,300,000)	(1,752,300,000)	(297,000,000.0)
Net ending balance	1,781,600,000	1,781,600,000	1,985,600,000	3,496,400,000
Asia Pacific
Goodwill [Roll Forward]
Gross beginning balance		1,294,600,000	1,312,400,000
Accumulated impairments	(414,100,000)	(414,100,000)	(414,100,000)	(124,500,000)
Net beginning balance		880,500,000	1,187,900,000
Acquisitions		0
Impairment charges		0	(289,600,000)
Measurement period adjustments			(2,700,000)
Foreign currency translation		(29,700,000)	(15,100,000)
Dispositions		(2,000,000.0)
Gross ending balance	1,262,900,000	1,262,900,000	1,294,600,000	1,312,400,000
Accumulated impairments	(414,100,000)	(414,100,000)	(414,100,000)	(124,500,000)
Net ending balance	$ 848,800,000	$ 848,800,000	$ 880,500,000	$ 1,187,900,000