GOODWILL AND INTANGIBLE ASSETS, NET - Schedule of Changes in Goodwill (Details) - USD ($) $ in Millions	12 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2023
Goodwill [Roll Forward]
Goodwill, gross		$ 3,469.4	$ 3,461.6
Additions	$ 44.5	41.8
Foreign currency translation and other	98.9	(34.0)
Fair value adjustments	(3.2)	0.0
Accumulated impairment losses	0.0	0.0
Goodwill, net	3,609.6	3,469.4
Investor Communication Solutions
Goodwill [Roll Forward]
Goodwill, gross		1,084.3	1,042.8
Additions	6.2	41.8
Foreign currency translation and other	3.4	(0.3)
Fair value adjustments	(3.2)	0.0
Accumulated impairment losses	0.0	0.0
Goodwill, net	1,090.7	1,084.3
Global Technology and Operations
Goodwill [Roll Forward]
Goodwill, gross		2,385.1	$ 2,418.8
Additions	38.3	0.0
Foreign currency translation and other	95.5	(33.7)
Fair value adjustments	0.0	0.0
Accumulated impairment losses	0.0	0.0
Goodwill, net	$ 2,518.9	$ 2,385.1