Segment and Related Information - Schedule of Segment Performance Based on Income (Loss) before Interest Income and Other Income and Expense (Detail) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019
Segment Reporting Information [Line Items]
Revenues	$ 164.0	$ 216.6	$ 545.4	$ 635.7
Depreciation and amortization	17.9	18.3	54.3	54.6
Segment operating income (loss)	(133.7)	5.9	(163.4)	13.2
Diagnostics [Member]
Segment Reporting Information [Line Items]
Revenues	150.5	200.5	503.6	592.5
Depreciation and amortization	16.8	17.0	50.5	50.7
Segment operating income (loss)	(93.6)	40.6	(46.2)	96.6
Other [Member]
Segment Reporting Information [Line Items]
Revenues	13.5	16.1	41.8	43.2
Depreciation and amortization	1.1	1.3	3.8	3.9
Segment operating income (loss)	$ (40.1)	$ (34.7)	$ (117.2)	$ (83.4)

The current period expense charged against earnings on long-lived, physical assets not used in production, and which are not intended for resale, to allocate or recognize the cost of such assets over their useful lives; or to record the reduction in book value of an intangible asset over the benefit period of such asset; or to reflect consumption during the period of an asset that is not used in production.

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