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Income Taxes - Additional Information (Detail) - USD ($) $ in Millions | 12 Months Ended
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Jun. 30, 2015 | Jun. 30, 2014
Income Taxes [Line Items] |  |
Amount of valuation allowance increased (decreased) | $ (8.0) | $ 33.2
Excess tax benefits realized | 3.4 | 11.1
Excess tax benefits attributable to deferred tax asset | 61.1 | 77.0
Deferred tax liability not recognized, Amount of unrecognized deferred tax liability, undistributed earnings of foreign subsidiaries | 0.0 |
Cumulative effect | $ 0.0 |
Income tax returns examination | The Company's New Jersey State income tax returns for the years ended June 30, 2007 through 2013 are currently under examination by the New Jersey State Division of Taxation and Finance. |
Crescendo Biosciences, Inc. |  |
Income Taxes [Line Items] |  |
Amount of valuation allowance increased (decreased) |  | 29.7
Utah |  |
Income Taxes [Line Items] |  |
Excess tax benefits attributable to deferred tax asset | $ 92.6 |
Remaining excess tax benefits not included in deferred tax assets | 137.3 |
Utah | Prior to the adoption of Statement 123(R) |  |
Income Taxes [Line Items] |  |
Excess tax benefits attributable to deferred tax asset | 3.0 |
South San Francisco, California |  |
Income Taxes [Line Items] |  |
Amount of valuation allowance increased (decreased) | (11.5) |
Foreign net operating losses and state tax research credits |  |
Income Taxes [Line Items] |  |
Amount of valuation allowance increased (decreased) | $ 3.5 |
Foreign (various jurisdictions) |  |
Income Taxes [Line Items] |  |
Amount of valuation allowance increased (decreased) |  | $ 3.5

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