Goodwill and Other Intangible Assets - Schedule of Identifiable Intangible Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 11,027	$ 12,130
Accumulated Amortization	(5,558)	(5,589)
Intangible Assets, Net	5,469	6,541
Proprietary adjuvant technology [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	7,597	8,357
Accumulated Amortization	(2,341)	(2,263)
Intangible Assets, Net	5,256	6,094
Collaboration agreements [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	3,430	3,773
Accumulated Amortization	(3,217)	(3,326)
Intangible Assets, Net	$ 213	$ 447