Collaboration Agreements - Additional Information (Details) - USD ($)	1 Months Ended				3 Months Ended	17 Months Ended	23 Months Ended
	Jul. 31, 2015	Apr. 30, 2015	May. 31, 2014	Apr. 30, 2014	Mar. 31, 2016	Mar. 31, 2016	Mar. 31, 2016	Dec. 31, 2015
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Deferred revenue					$ 15,046,000	$ 15,046,000	$ 15,046,000	$ 15,046,000
Pharma License Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue recognized for milestones					0
Pharma License Agreement | Upfront Non-refundable Cash Payment
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Payments received under collaboration agreement				$ 15,000,000
Pharma License Agreement | Post Acquisition Revenue | Upfront Non-refundable Cash Payment
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue recognized					0
Pharma License Agreement | Maximum | Product Candidate | Development Milestone Contingent Payments
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Milestone amount eligible to receive for products or product candidates					156,000,000
Pharma License Agreement | Maximum | Product | Commercial and Net Sales Contingent Milestone Payments
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Milestone amount eligible to receive for products or product candidates					135,000,000
Novartis Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue recognized					$ 3,700,000
Novartis share of joint development costs					38.00%
Period after first commercial sale of product on which Novartis' royalty obligation run on a country to country basis					12 years
Estimated performance period of agreement	13 years 6 months
Deferred revenue					$ 188,900,000	188,900,000	188,900,000
Novartis Agreement | United States
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Collaborative arrangement profit share percentage					50.00%
Novartis Agreement | European Countries and Japan
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Collaborative arrangement profit share percentage					45.00%
Novartis Agreement | United States, Specified European Countries and /or Japan
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Collaborative Agreement, Obligations					With respect to the United States, specified European countries and/or Japan, the Company may elect for such region to either reduce by 50% or to eliminate in full the Company’s development and commercialization cost sharing obligation. If the Company elects to reduce its cost sharing percentage by 50% in any such region, then its profit share in such region will also be reduced by 50%. If the Company elects to eliminate its development cost sharing obligation, then such region will be removed from the profit share, and instead Novartis will owe the Company royalties on any net sales of product for such region, as described above.
Reduction percentage of development cost share					50.00%
Reduction percentage of profit share					50.00%
Novartis Agreement | Novartis
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Novartis share of joint development costs					62.00%
Collaborative arrangement profit share percentage					50.00%
Novartis Agreement | Up Front Payment Arrangement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Payments received under collaboration agreement		$ 200,000,000
Novartis Agreement | Maximum | Development Milestone
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Milestone amount eligible to receive					$ 250,000,000
Novartis Agreement | Maximum | Regulatory Approval Milestone
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Milestone amount eligible to receive					250,000,000
Janssen ADU-214 Agreement | Up Front Payment Arrangement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Payments received under collaboration agreement						30,000,000
Janssen ADU-214 Agreement | Non Substantive And Substantive Milestone
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Payments received under collaboration agreement						$ 11,000,000
Janssen ADU-214 Agreement | Maximum | Contingent Payments
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Milestone amount eligible to receive					766,000,000
Janssen ADU-741 Agreements | Up Front Payment Arrangement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Payments received under collaboration agreement							12,000,000
Janssen ADU-741 Agreements | Non Substantive And Substantive Milestone
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Payments received under collaboration agreement							$ 10,000,000
Janssen ADU-741 Agreements | Maximum | Contingent Payments
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Milestone amount eligible to receive					343,000,000
Janssen GVAX Prostate Agreement | Up Front Payment Arrangement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Payments received under collaboration agreement			$ 500,000
Janssen GVAX Prostate Agreement | Specified Commercial Milestone
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Milestone amount eligible to receive					2,000,000
Janssen ADU-741 and Janssen GVAX Prostate Agreement | Up Front Payment Arrangement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Payments received under collaboration agreement					$ 12,500,000