COMMITMENTS AND CONTINGENCIES (Details) $ in Thousands	1 Months Ended		3 Months Ended		6 Months Ended
	Dec. 31, 2013	Apr. 30, 2012 ft² item	Jun. 30, 2015 USD ($)	Jun. 30, 2014 USD ($)	Jun. 30, 2015 USD ($)	Jun. 30, 2014 USD ($)	Dec. 31, 2014 USD ($)
Non-Cancelable Operating Lease
2015 (remainder)			$ 2,060		$ 2,060
2016			4,030		4,030
2017			3,287		3,287
2018			2,371		2,371
2019			1,575		1,575
Thereafter			4,866		4,866
Total future minimum lease payments			18,189		18,189
Office and laboratory
Non-Cancelable Operating Lease
Rent expense			300	$ 200	700	$ 300
Lease of cars
Non-Cancelable Operating Lease
Rent expense			500	$ 0	1,000	$ 0
New lease Newark
Non-Cancelable Operating Lease
Total future minimum lease payments			11,600		11,600
Square feet agreed to lease | ft²		52,500
Additional square feet the Company will lease | ft²		8,000
Number of lease renewal terms | item		1
Lease renewal option period		5 years
Lease renewal, minimum notice period prior to lease expiration		12 months
Lease termination penalty interest (as a percent)		8.00%
Deferred rent			1,700		1,700		$ 1,700
Enterprise
Non-Cancelable Operating Lease
Total future minimum lease payments			$ 6,600		$ 6,600
Enterprise | Minimum
Non-Cancelable Operating Lease
Lease terms	18 months
Enterprise | Maximum
Non-Cancelable Operating Lease
Lease terms	36 months