INTANGIBLE ASSETS AND GOODWILL (Details) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Intangible Assets and Goodwill
Goodwill	$ 8,965,000us-gaap_Goodwill	$ 8,965,000us-gaap_Goodwill
Finite-lived intangible asset
Accumulated Amortization	(5,789,000)	(4,776,000)
Total Intangible Assets
Cost of total intangible assets	27,596,000	27,596,000
Intangible Assets, Net (Excluding Goodwill)	21,807,000	22,820,000
Amortization expense for intangible assets	1,013,000us-gaap_AmortizationOfIntangibleAssets	1,013,000us-gaap_AmortizationOfIntangibleAssets	1,090,000us-gaap_AmortizationOfIntangibleAssets
Estimated future amortization expense of intangible assets
2015	1,000,000
2016	1,000,000
2017	900,000
2018	900,000
2019	900,000
Amgen Amendment
Finite-lived intangible asset
Estimated Life	16 years
Cost	14,500,000	14,500,000
Accumulated Amortization	(4,708,000)	(3,812,000)
Net	9,792,000	10,688,000
Core Technology
Finite-lived intangible asset
Estimated Life	11 years
Cost	1,296,000	1,296,000
Accumulated Amortization	(1,081,000)	(964,000)
Net	215,000	332,000
IPR&D
Indefinite-lived intangible assets:
Indefinite-lived intangible assets	$ 11,800,000	$ 11,800,000

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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(2)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

+ Details

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- Definition

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

+ Details

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- Definition

Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References