Goodwill and Intangible Assets, Net - Schedule of Changes in Goodwill (Details) - USD ($) $ in Millions	12 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Sep. 30, 2019	Jun. 30, 2018
Goodwill [Roll Forward]
Goodwill, gross		$ 1,500.0		$ 1,254.9
Transfers		0.0
Additions	$ 201.5	247.7
Fair value adjustments	(9.0)	7.4
Foreign currency translation and other	(18.1)	(10.0)
Accumulated impairment losses	0.0	0.0
Goodwill	1,674.5	1,500.0
Investor Communication Solutions
Goodwill [Roll Forward]
Goodwill, gross		913.1		884.4
Transfers		(2.8)
Additions	131.6	27.3
Fair value adjustments	(0.2)	7.4
Foreign currency translation and other	(5.1)	(3.2)
Accumulated impairment losses	0.0	0.0
Goodwill	1,039.5	913.1	$ (2.8)
Global Technology and Operations
Goodwill [Roll Forward]
Goodwill, gross		586.9		$ 370.5
Transfers		2.8
Additions	69.9	220.4
Fair value adjustments	(8.8)	0.0
Foreign currency translation and other	(13.0)	(6.8)
Accumulated impairment losses	0.0	0.0
Goodwill	$ 635.0	$ 586.9	$ 2.8

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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