COMMITMENTS AND CONTINGENCIES (Details) (Cambridge Lease, USD $) In Thousands, unless otherwise specified	0 Months Ended
	Nov. 29, 2011 item sqft	Mar. 31, 2015	Nov. 29, 2011 sqft
Cambridge Lease
Commitments
Lease Space for Laboratory and office space (in square feet)	26,150		26,150
Term of commercial lease	6 years 3 months
Number of lease extension options	1
Term of lease extension option	5 years
Standby letter of credit	$ 311		$ 311
Deferred rent liability		$ 459