License and Research Collaboration Agreements (Notes)	3 Months Ended
Mar. 31, 2016
Revenue Recognition [Abstract]
Licensing and Research Collaboration Agreements [Text Block]	License and Research Collaboration Agreements Genentech, a Member of the Roche Group In October 2014, the Company entered into an exclusive worldwide collaboration and license agreement with Genentech, or the Genentech Agreement, for the development and commercialization of GDC-0919, one of the Company's clinical stage IDO pathway inhibitors. The parties also entered into a research collaboration for the discovery of next generation IDO and TDO pathway inhibitors to be developed and commercialized under this agreement. Under the terms of the Genentech Agreement, the Company received a nonrefundable upfront cash payment of $150.0 million from Genentech in 2014 and is eligible to receive additional payments of over $1.0 billion upon achieving certain GDC-0919 and Next Generation Product Development regulatory development, international patent acceptance, country marketing approval, and sales-based milestones. The Company retains the right to exercise an option to co-promote GDC-0919 and any subsequent products for the U.S. market and is also eligible to receive escalating double digit royalty payments on potential commercial sales of multiple products by Genentech. For the three months ended March 31, 2016, the Company recognized license and collaboration revenue under the Genentech Agreement of $807,000, including $598,000 for amounts received as reimbursement for the Company's employees working on the project, $167,000 for providing an alliance manager, and $42,000 for participation in the joint research committee (JRC). For the three months ended March 31, 2015, the Company recognized license and collaboration revenue under the Genentech agreement of $10.1 million, including $9.4 million for program materials and technology transfer, $677,000 for amounts received as reimbursement for the Company's employees working on the project, and $42,000 for participation in the JRC. In accordance with the Company’s continuing performance obligation, $1.0 million of the $150.0 million upfront payment remains deferred as of March 31, 2016 and will be recognized in future periods. The upfront payment provides no general right of return for any non-contingent deliverable and no portion of any revenue recognized is refundable. Merck Sharp & Dohme Corp. In November 2014, the Company entered into a licensing and collaboration agreement with Merck, or the Merck Agreement, to develop, manufacture and commercialize rVSV-ZEBOV GP, an Ebola vaccine the Company licensed from the Public Health Agency of Canada, or PHAC. Under the terms of the Merck Agreement, the Company granted Merck an exclusive, royalty bearing license to rVSV-ZEBOV GP and related technology. Under the Merck Agreement, the Company received a $30.0 million non-refundable, upfront payment in December 2014, and a one-time $20.0 million non-refundable milestone payment in February 2015 upon the initiation of the pivotal clinical trial using the current rVSV-ZEBOV GP vaccine product as one arm of the trial. In addition, the Company can receive escalating royalties on potential commercial sales by Merck of the current product candidate ranging from single digit to double digits on the rVSV-ZEBOV GP license agreement product sales and escalating royalties on potential commercial sales by Merck of products other than current products within the Company’s patent rights ranging from low to high single digit, on increasing levels of annual net sales worldwide. Merck will lead the development of rVSV-ZEBOV GP and any other rVSV-based viral hemorrhagic fever vaccine product candidates in order to create a marketable product safe for human use. For the three months ended March 31, 2016, the Company recognized license and collaboration revenues of $561,000, for the reimbursement of costs not covered under government contracts. For the three months ended March 31, 2015, the Company recognized license and collaboration revenue under the Merck Agreement of $20.0 million associated with the one-time non-refundable milestone payment. In accordance with the Company’s continuing performance obligations, $51,000 of the $30.0 million upfront payment remains deferred as of March 31, 2016 and will be recognized in future periods. The upfront payment provides no general right of return for any non-contingent deliverable, and no portion of any revenue recognized is refundable.

License and Research Collaboration Agreements

Genentech, a Member of the Roche Group

In October 2014, the Company entered into an exclusive worldwide collaboration and license agreement with Genentech, or the Genentech Agreement, for the development and commercialization of GDC-0919, one of the Company's clinical stage IDO pathway inhibitors. The parties also entered into a research collaboration for the discovery of next generation IDO and TDO pathway inhibitors to be developed and commercialized under this agreement. Under the terms of the Genentech Agreement, the Company received a nonrefundable upfront cash payment of $150.0 million from Genentech in 2014 and is eligible to receive additional payments of over $1.0 billion upon achieving certain GDC-0919 and Next Generation Product Development regulatory development, international patent acceptance, country marketing approval, and sales-based milestones. The Company retains the right to exercise an option to co-promote GDC-0919 and any subsequent products for the U.S. market and is also eligible to receive escalating double digit royalty payments on potential commercial sales of multiple products by Genentech.

For the three months ended March 31, 2016, the Company recognized license and collaboration revenue under the Genentech Agreement of $807,000, including $598,000 for amounts received as reimbursement for the Company's employees working on the project, $167,000 for providing an alliance manager, and $42,000 for participation in the joint research committee (JRC). For the three months ended March 31, 2015, the Company recognized license and collaboration revenue under the Genentech agreement of $10.1 million, including $9.4 million for program materials and technology transfer, $677,000 for amounts received as reimbursement for the Company's employees working on the project, and $42,000 for participation in the JRC. In accordance with the Company’s continuing performance obligation, $1.0 million of the $150.0 million upfront payment remains deferred as of March 31, 2016 and will be recognized in future periods. The upfront payment provides no general right of return for any non-contingent deliverable and no portion of any revenue recognized is refundable.

Merck Sharp & Dohme Corp.

In November 2014, the Company entered into a licensing and collaboration agreement with Merck, or the Merck Agreement, to develop, manufacture and commercialize rVSV-ZEBOV GP, an Ebola vaccine the Company licensed from the Public Health Agency of Canada, or PHAC. Under the terms of the Merck Agreement, the Company granted Merck an exclusive, royalty bearing license to rVSV-ZEBOV GP and related technology. Under the Merck Agreement, the Company received a $30.0 million non-refundable, upfront payment in December 2014, and a one-time $20.0 million non-refundable milestone payment in February 2015 upon the initiation of the pivotal clinical trial using the current rVSV-ZEBOV GP vaccine product as one arm of the trial. In addition, the Company can receive escalating royalties on potential commercial sales by Merck of the current product candidate ranging from single digit to double digits on the rVSV-ZEBOV GP license agreement product sales and escalating royalties on potential commercial sales by Merck of products other than current products within the Company’s patent rights ranging from low to high single digit, on increasing levels of annual net sales worldwide. Merck will lead the development of rVSV-ZEBOV GP and any other rVSV-based viral hemorrhagic fever vaccine product candidates in order to create a marketable product safe for human use.

For the three months ended March 31, 2016, the Company recognized license and collaboration revenues of $561,000, for the reimbursement of costs not covered under government contracts. For the three months ended March 31, 2015, the Company recognized license and collaboration revenue under the Merck Agreement of $20.0 million associated with the one-time non-refundable milestone payment. In accordance with the Company’s continuing performance obligations, $51,000 of the $30.0 million upfront payment remains deferred as of March 31, 2016 and will be recognized in future periods. The upfront payment provides no general right of return for any non-contingent deliverable, and no portion of any revenue recognized is refundable.