Goodwill and Intangibles Assets, net - Changes In Goodwill (Details) - USD ($) $ in Millions	9 Months Ended
Mar. 31, 2020	Jun. 30, 2019
Goodwill [Roll Forward]
Goodwill	$ 2,299.3	$ 2,323.0
Additions and other adjustments	(2.5)
Currency translation adjustments	(21.2)
Balance at March 31, 2020	2,299.3
Employer Services
Goodwill [Roll Forward]
Goodwill	2,294.5	2,318.2
Additions and other adjustments	(2.5)
Currency translation adjustments	(21.2)
Balance at March 31, 2020	2,294.5
PEO Services
Goodwill [Roll Forward]
Goodwill	4.8	$ 4.8
Additions and other adjustments	0.0
Currency translation adjustments	0.0
Balance at March 31, 2020	$ 4.8

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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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of increase (decrease) 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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