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Goodwill and Intangible Assets - Changes in Carrying Amount of Good (Detail) - USD ($) $ in Millions	12 Months Ended
	Jun. 30, 2020	Jun. 30, 2019
Goodwill And Intangible Assets [Line Items]
Beginning balance	$ 417.2	$ 318.6
Acquisitions		94.9
Adjustments to acquisitions		4.4
Goodwill deconsolidated on sale of Clinic	(7.3)
Goodwill impairment charge	(82.0)
Translation adjustments	(0.3)	(0.7)
Ending balance	327.6	417.2
Diagnostic [Member]
Goodwill And Intangible Assets [Line Items]
Beginning balance	351.6	252.8
Acquisitions		94.9
Adjustments to acquisitions		4.4
Goodwill impairment charge	(80.7)
Translation adjustments	(0.2)	(0.5)
Ending balance	270.7	351.6
Other [Member]
Goodwill And Intangible Assets [Line Items]
Beginning balance	65.6	65.8
Goodwill deconsolidated on sale of Clinic	(7.3)
Goodwill impairment charge	(1.3)
Translation adjustments	(0.1)	(0.2)
Ending balance	$ 56.9	$ 65.6

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Goodwill and intangible assets.

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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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