Other Long-Term Liablilities (Details 2) - USD ($) $ in Thousands	1 Months Ended		3 Months Ended		6 Months Ended
	May. 31, 2014	Sep. 30, 2013	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
REVENUE
Contracts and Grants			$ 1,844	$ 392	$ 1,988	$ 773
Rockefeller Development Services Agreement
REVENUE
Term of the agreement		3 years
Upfront payment recognized as revenue over the term of the agreement		$ 1,300
Contracts and Grants			1,500	400	1,600	700
Bristol Meyers Collaborative Arrangement
REVENUE
Term of the agreement	5 years
Upfront payment recognized as revenue over the term of the agreement	$ 5,000
Contracts and Grants			$ 300	$ 200	$ 600	$ 200
Reimbursement of external costs incurred by the company (as a percent)	50.00%