T-Cell Factory Acquisition - Schedule of Calculation of Purchase Price (Details) - Jun. 30, 2015 - T-Cell Factory Acquisition - USD ($) $ in Thousands	Total
Business Acquisition Equity Interests Issued Or Issuable [Line Items]
Cash and stock consideration	$ 19,260
Contingent consideration	16,622
Working capital adjustment	(59)
Business Combination, Consideration Transferred	$ 35,823