Collaboration Agreements - Additional Information (Details)	1 Months Ended				3 Months Ended	12 Months Ended			18 Months Ended
	Jul. 31, 2015	Apr. 30, 2015 USD ($)	Feb. 28, 2015 Product	May 31, 2014 USD ($)	Jun. 30, 2016 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Oct. 31, 2015 USD ($)	Oct. 31, 2015 USD ($)
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Deferred revenue						$ 15,052,000	$ 15,046,000
Duo Body Product
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Number of product candidates | Product			5
Percentage of development cost share			50.00%
Novartis Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue recognized for milestones						$ 35,000,000
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
Revenue recognized						$ 14,800,000	7,400,000
Deferred revenue						$ 177,800,000	192,600,000
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 | Development Milestone
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue recognized for milestones					$ 35,000,000
Novartis Agreement | Maximum | Development Milestone
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Milestone amount eligible to receive						$ 215,000,000
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
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue recognized for milestones							21,000,000
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							21,000,000
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
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue recognized for milestones							$ 10,000,000
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
Merck License Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue recognized for milestones						0
Merck License Agreement | Maximum | Development Milestone Contingent Payments | Product Candidate
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Milestone amount eligible to receive for products or product candidates						312,000,000
Merck License Agreement | Maximum | Commercial And Net Sales Contingent Milestone Payments | Product
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Milestone amount eligible to receive for products or product candidates						$ 135,000,000