Goodwill and Intangible Assets (Schedule of Identifiable Intangible Assets) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 12,592	$ 13,884
Accumulated Amortization	(1,394)	(1,307)
Intangible Assets, Net	11,198us-gaap_FiniteLivedIntangibleAssetsNet	12,577us-gaap_FiniteLivedIntangibleAssetsNet
Collaboration agreements [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	3,917	4,319
Accumulated Amortization	(672)	(629)
Intangible Assets, Net	3,245	3,690
Proprietary adjuvant technology [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	8,675	9,565
Accumulated Amortization	(722)	(678)
Intangible Assets, Net	$ 7,953	$ 8,887

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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

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

+ References

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

+ References

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