License Agreement (Details) - Pfizer, Inc. - License Agreement $ in Millions	Mar. 31, 2015 USD ($) shares
License Agreements
Percentage of shares of common stock offering issued to Pfizer	15.00%
Common Stock
License Agreements
Issuance of stock (in shares) \| shares	675,250
Issuance of common stock	$ 0.9
Common Stock \| Minimum
License Agreements
Ownership by Pfizer	5.00%
Milestone Payments \| Maximum
License Agreements
Potential payments upon achievement of certain milestones	$ 37.0

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