PROPERTY AND EQUIPMENT, NET (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Property and equipment
Total Property and Equipment	$ 24,755us-gaap_PropertyPlantAndEquipmentGross	$ 21,965us-gaap_PropertyPlantAndEquipmentGross
Less Accumulated Depreciation and Amortization	(14,220)	(11,992)
Property and Equipment, Net	10,535us-gaap_PropertyPlantAndEquipmentNet	9,973us-gaap_PropertyPlantAndEquipmentNet
Depreciation and amortization expense	2,388	1,932	2,047
Laboratory Equipment
Property and equipment
Total Property and Equipment	4,223	3,699
Manufacturing Equipment
Property and equipment
Total Property and Equipment	2,274	2,130
Office Furniture and Equipment
Property and equipment
Total Property and Equipment	1,888	1,386
Leasehold Improvements
Property and equipment
Total Property and Equipment	14,603	14,493
Construction in Progress
Property and equipment
Total Property and Equipment	$ 1,767	$ 257

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

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

-Publisher FASB

-Name Accounting Standards Codification

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-Section S99

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-Subparagraph (SX 210.5-02.14)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

-Publisher SEC

-Name Regulation S-X (SX)

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- Definition

The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

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-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

-Publisher SEC

-Name Regulation S-X (SX)

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

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