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Acquisition - Allocation of Consideration Transferred for Crescendo (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Jun. 30, 2014	Feb. 28, 2014
Business Acquisition [Line Items]
Goodwill	$ 185,228us-gaap_Goodwill	$ 169,181us-gaap_Goodwill
Crescendo Biosciences, Inc.
Business Acquisition [Line Items]
Other assets acquired			15,826
Intangible assets			196,600
Goodwill			112,331
Total assets acquired			324,757
Deferred tax liability			44,213
Other liabilities assumed			21,594
Total net assets acquired			$ 258,950