Acquisition of Novavax AB (Narrative) (Details) (USD $)	6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013	Dec. 31, 2012	Jun. 30, 2014 Novavax AB [Member]	Jul. 31, 2013 Novavax AB [Member]
Business Acquisition [Line Items]
Shares acquired in Novavax AB					0.50%
Goodwill before retroactive adjustment						$ 26,200,000
Ownership percentage	20.00%
Goodwill	57,906,000	33,141,000	58,707,000	33,141,000		25,400,000
Currency translation and other adjustments	$ (801,000)