INTANGIBLE ASSETS AND GOODWILL (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Intangible Assets and Goodwill
Goodwill	$ 8,965	$ 8,965
Finite-lived intangible asset
Accumulated Amortization	(6,802)	(5,789)
Total Intangible Assets
Cost of total intangible assets	27,596	27,596
Intangible Assets, Net (Excluding Goodwill)	20,794	21,807
Amortization expense for intangible assets	1,013	1,013	$ 1,013
Estimated future amortization expense of intangible assets
2016	1,000
2017	900
2018	900
2019	900
2020	$ 900
Amgen Amendment
Finite-lived intangible asset
Estimated Life	16 years
Cost	$ 14,500	14,500
Accumulated Amortization	(5,605)	(4,708)
Net	$ 8,895	9,792
Core Technology
Finite-lived intangible asset
Estimated Life	11 years
Cost	$ 1,296	1,296
Accumulated Amortization	(1,197)	(1,081)
Net	99	215
IPR&D
Indefinite-lived intangible assets:
Indefinite-lived intangible assets	$ 11,800	$ 11,800