License and Collaborative Agreements (Details) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2005	May 18, 2011
License and Collaborative Agreements [Abstract]
License fee revenue	$ 0	$ 1,002,000	$ 4,000
License purchase option price						11,500,000
Compensation earned under research funding agreements with CFFT				2,200,000	1,700,000
Royalty payable on approval of Arikace as commercialized drug	13,400,000
Royalty payment period	3 years
Period for meeting sales milestones for additional royalty payments	5 years
Royalty payable on meeting certain sales milestones	$ 3,900,000