License and Collaboration Agreements - Additional Information (Detail) (USD $)	12 Months Ended				3 Months Ended	0 Months Ended	12 Months Ended			0 Months Ended				12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2013 Actavis [Member]	Mar. 31, 2013 License and Collaboration Agreements [Member] GTC [Member]	May 05, 2011 License and Collaboration Agreements [Member] PharmaEngine [Member]	Dec. 31, 2013 License and Collaboration Agreements [Member] PharmaEngine [Member]	Dec. 31, 2012 License and Collaboration Agreements [Member] PharmaEngine [Member]	Dec. 31, 2011 License and Collaboration Agreements [Member] PharmaEngine [Member]	May 05, 2011 License and Collaboration Agreements [Member] PharmaEngine [Member] Development and Regulatory Milestone [Member]	May 05, 2011 License and Collaboration Agreements [Member] PharmaEngine [Member] Sales Milestones [Member]	May 05, 2012 License and Collaboration Agreements [Member] PharmaEngine [Member] Phase 3 Clinical Trial in Pancreatic Cancer [Member]	Nov. 10, 2009 License and Collaboration Agreements [Member] Sanofi [Member]	Dec. 31, 2013 License and Collaboration Agreements [Member] Sanofi [Member]	Dec. 31, 2010 License and Collaboration Agreements [Member] Sanofi [Member] Phase 2 Clinical Trial in Breast Cancer [Member]	Dec. 31, 2011 License and Collaboration Agreements [Member] Sanofi [Member] Phase 2 Clinical Trial in Non-small Cell Lung Cancer [Member]	Dec. 31, 2012 License and Collaboration Agreements [Member] Sanofi [Member] Phase 2 Clinical Trial in Ovarian Cancer [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Upfront license fee received													$ 60,000,000
Milestone payments received				15,500,000										25,000,000	10,000,000	10,000,000	5,000,000
Budget period														12 months
Expected development period from the effective date of agreement													12 years
Development services performed														10,100,000
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	147,139,000	125,858,000	100,630,000				1,500,000	6,200,000	11,200,000
Milestone payment expensed								5,000,000
Milestone payment expense									10,000,000
Amounts accrued and payable related to the agreement							600,000	300,000
Milestone license fee received				2,000,000
Agreement expiration term respect to each product				10 years
Additional renewal term				2 years
Notice period of termination				90 days
Milestones and development expenses				2,100,000
Deferred revenue recognized due to a change in estimate of expected development term					$ 600,000