Segment and Related Information - Segment Performance Based on Income (Loss) before Interest Income and Other Income and Expense (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2015	Mar. 31, 2014
Segment Reporting Information [Line Items]
Revenue	$ 179,985us-gaap_Revenues	$ 182,924us-gaap_Revenues	$ 533,216us-gaap_Revenues	$ 589,450us-gaap_Revenues
Depreciation and amortization	6,399us-gaap_DepreciationAndAmortization	3,479us-gaap_DepreciationAndAmortization	18,389us-gaap_DepreciationAndAmortization	8,291us-gaap_DepreciationAndAmortization
Segment operating income (loss)	35,740us-gaap_OperatingIncomeLoss	55,287us-gaap_OperatingIncomeLoss	98,002us-gaap_OperatingIncomeLoss	221,188us-gaap_OperatingIncomeLoss
Molecular Diagnostics
Segment Reporting Information [Line Items]
Revenue	172,978	176,191	516,634	565,335
Depreciation and amortization	5,207	2,506	15,176	5,335
Segment operating income (loss)	55,198	70,815	159,299	266,794
Pharmaceutical and Clinical Services
Segment Reporting Information [Line Items]
Revenue	7,007	6,733	16,582	24,115
Depreciation and amortization	566	471	1,465	1,462
Segment operating income (loss)	(1,147)	(73)	(3,941)	2,816
Research
Segment Reporting Information [Line Items]
Depreciation and amortization	626	502	1,748	1,494
Segment operating income (loss)	$ (18,311)	$ (15,455)	$ (57,356)	$ (48,422)

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=31042434&loc=d3e3602-108585

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- Definition

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

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Article 5

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