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Subsequent Event - Additional Information (Details) - Jul. 31, 2015 - Subsequent Event [Member] - USD ($) $ / shares in Units, $ in Millions	Total
Subsequent Event [Line Items]
Stock Issued During Period, Value, New Issues	$ 141.0
Stock issued during the period for new issue	3,525,000
Clinical milestone	$ 10.0
Common stock price per share	$ 37.00
Operating Leases, Future Minimum Payments Due	$ 14.6
Amounts received and deferred under operating lease	$ 5.1
Over-Allotment Option [Member]
Subsequent Event [Line Items]
Stock issued during the period for new issue	528,750

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- Definition

Amounts received and deferred from lessor related to operating lease

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