Segment and Related Information - Schedule of Segment Performance Based on Income (Loss) before Interest Income and Other Income and Expense (Detail) - USD ($) $ in Millions	12 Months Ended
Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2013
Segment Reporting Information [Line Items]
Revenues	$ 723.1	$ 778.2	$ 613.2
Depreciation and amortization	25.0	13.8	8.9
Segment operating income (loss)	134.2	274.4	228.0
Diagnostics
Segment Reporting Information [Line Items]
Revenues	695.5	748.2	582.4
Depreciation and amortization	20.5	9.9	5.0
Segment operating income (loss)	217.1	338.0	291.5
Other
Segment Reporting Information [Line Items]
Revenues	27.6	30.0	30.8
Depreciation and amortization	4.5	3.9	3.9
Segment operating income (loss)	$ (82.9)	$ (63.6)	$ (63.5)

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

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The net result for the period of deducting operating expenses from operating revenues.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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