U.S. Government Agreement, Joint Venture and Collaborations (Narrative) (Details) - USD ($) $ in Thousands	1 Months Ended			12 Months Ended			42 Months Ended	59 Months Ended
	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2015	Dec. 31, 2015	Sep. 30, 2014	Feb. 28, 2011
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Ownership percentage				20.00%			20.00%	20.00%
Government contracts				$ 33,344	$ 26,213	$ 17,708		$ 112,000
Research and development collaborations				$ 2,906	$ 4,446	$ 3,207
Cadila [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Joint Venture Percentage Owned By Others				80.00%			80.00%	80.00%
HHS BARDA Contract [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Government contracts			$ 3,100
Government Contract Receivable									$ 97,000
Increase in funding for recovery of additional costs under contract		$ 7,700
HHS BARDA Option for Additional Period [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Contract term				2 years
Government Contract Receivable									$ 70,000
License Agreement with LG Life Sciences, Ltd. [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Upfront license payment										$ 2,500
PATH Vaccine Solutions [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Research and development collaborations				$ 500			$ 6,800
Bill Melinda Gates Foundation [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Grant agreement	$ 89,100			$ 1,600