U.S. Government Agreement and Collaborations (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended				1 Months Ended	6 Months Ended	16 Months Ended	29 Months Ended	1 Months Ended		1 Months Ended	6 Months Ended	12 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Feb. 28, 2011	Jun. 30, 2013 Cadila [Member]	Feb. 28, 2011 HHS BARDA Contract [Member]	Jun. 30, 2013 HHS BARDA Contract [Member]	Jun. 30, 2013 HHS BARDA Contract [Member]	Jun. 30, 2013 HHS BARDA Contract [Member]	Feb. 28, 2011 HHS BARDA Option for Additional Period [Member]	Feb. 28, 2011 License Agreement with LG Life Sciences, Ltd. [Member]	Jul. 31, 2012 PATH Vaccine Solutions [Member]	Jun. 30, 2013 PATH Vaccine Solutions [Member]	Jun. 30, 2013 PATH Vaccine Solutions [Member]	Aug. 08, 2013 PATH Vaccine Solutions [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Contract receivable					$ 179,000		$ 97,000				$ 82,000
Contract term							3 years				2 years
Government contracts	3,276	7,103	6,717	11,745				6,500		41,000
Research and development collaborations	255		648										2,000	600	1,900
Research and development collaboration increase																300
Trial costs incurred									2,900
Upfront license payment												$ 2,500
Ownership percentage	20.00%		20.00%
Joint Venture Percentage Owned By Others						80.00%