License and Collaboration Agreements - Additional Information (Detail) (USD $)	3 Months Ended		0 Months Ended	3 Months Ended		12 Months Ended	0 Months Ended				3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Nov. 10, 2009 Sanofi [Member]	Mar. 31, 2014 Sanofi [Member]	Mar. 31, 2014 Actavis [Member]	Dec. 31, 2013 Actavis [Member]	May 05, 2011 PharmaEngine [Member]	May 05, 2011 PharmaEngine [Member] Development and Regulatory Milestone [Member]	May 05, 2011 PharmaEngine [Member] Sales Milestone [Member]	May 05, 2011 PharmaEngine [Member] Phase 3 Clinical Trial in Pancreatic Cancer [Member]	Mar. 31, 2014 License and Collaboration Agreements [Member] Sanofi [Member]	Mar. 31, 2014 License and Collaboration Agreements [Member] PharmaEngine [Member]	Mar. 31, 2013 License and Collaboration Agreements [Member] PharmaEngine [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Upfront license fee received			$ 60,000,000
Milestone license fee received				25,000,000		2,000,000
Budget period											12 months
Expected development period from the effective date of agreement			12 years
Development services performed											5,800,000
Upfront license fees paid							10,000,000
Maximum milestone payment obligation								80,000,000	130,000,000
Milestone payment										5,000,000
Research and development expenses	30,324,000	36,989,000										100,000	300,000
Eligible milestone payments						15,500,000
Agreement expiration term respect to each product					10 years
Additional renewal term					2 years
Notice period of termination					90 days
Milestones and development expenses					$ 2,600,000