Legal Proceedings	9 Months Ended
Sep. 30, 2015
Commitments and Contingencies Disclosure [Abstract]
Legal Proceedings	Legal Proceedings TheraVectys SA v. Immune Design Corp. In October 2013, TheraVectys SA, or TVS, a French biotechnology company, filed a complaint against us in the United States District Court for the District of Delaware. TVS alleged that it had entered into a contractual relationship with Henogen SA, or Henogen, in 2010 with respect to the production of lentiviral vector vaccines for TVS. Henogen is a contract manufacturing organization with which we contracted for the manufacture of our LV305 product candidate. TVS alleged that its contractual relationship with Henogen contained an exclusivity provision limiting Henogen’s ability to participate in the manufacturing process of a vaccine based on lentiviral DNA vectors for third parties, as well as a provision preventing Henogen from sharing or using certain TVS confidential technology for manufacturing processes developed by TVS with or for the benefit of others. TVS alleged that we entered into a contractual relationship with Henogen in 2012 to manufacture lentiviral vectors for vaccines, which TVS contends interfered with its contract with Henogen and resulted in the use of certain TVS confidential information and trade secrets. The complaint asserted three counts for relief: tortious interference with contractual relationship, unfair competition and misappropriation of trade secrets. TVS did not specify its claimed damages, other than to assert that they exceed $75,000. TVS also requested in its complaint injunctive relief enjoining us from importing, receiving, possessing or using lentiviral vector vaccines developed or produced by Henogen, but never filed a motion seeking injunctive relief. The parties entered into several stipulations extending the deadline for us to respond to the complaint. On or about April 7, 2014, TVS filed a Notice of Voluntary Dismissal without prejudice of this lawsuit. On or about July 24, 2014, shortly after our Registration Statement on Form S-1 was declared effective by the SEC for our initial public offering, TVS filed a new complaint against us in the Chancery Court of the State of Delaware, alleging facts substantially similar to the prior complaint. In addition, the complaint further alleges that we obtained shipments of lentiviral vectors for vaccines from Henogen and are conducting clinical trials with these lentiviral vectors. The complaint asserts four counts for relief: tortious interference with contractual relationship, unfair competition, misappropriation of trade secrets, and unjust enrichment; claimed damages were not specified. The complaint also requested injunctive relief enjoining us from using lentiviral vectors developed or produced by Henogen, using any other materials or information obtained by Henogen, and citing to the FDA or otherwise relying on any clinical trials using lentiviral vector vaccines developed or produced by Henogen. On or about July 24, 2014, TVS also filed a motion for expedited proceedings in support of an anticipated motion for preliminary injunction. On August 8, 2014 the court granted TVS’ motion for expedited proceedings and set a hearing date in mid-November 2014 for TVS’ anticipated motion for preliminary injunction. In September 2014, TVS filed a motion to postpone the hearing date and delay the proceedings it previously sought to expedite. The court granted the motion and set a new date for the hearing. On or about December 15, 2014, TVS filed a motion for a preliminary injunction seeking, among other things, to enjoin us from making any use of lentiviral vectors pending final resolution of the litigation. A hearing was held on TVS’s motion in January 2015. By order dated March 9, 2015, the Chancery Court denied TVS’ motion for a preliminary injunction. The court has not yet made any final determination on the merits of the lawsuit, which will be determined at a full trial. A trial date has not yet been set. On September 29 and 30, 2015, TVS and we participated in a voluntary non-binding mediation. However, to date we have not reached any agreement with TVS to settle this lawsuit and we may not be able to resolve the matter through mediation, in which case we intend to continue to vigorously defend this lawsuit. Due to the nature of the litigation and developments to date, we view a potential loss arising from this matter as reasonably possible. However, due to unresolved questions and issues that are critical to achieving settlement of this matter, if any, we cannot make a reasonable estimate of a potential loss, or range of loss, at this time.

Legal Proceedings

TheraVectys SA v. Immune Design Corp.

In October 2013, TheraVectys SA, or TVS, a French biotechnology company, filed a complaint against us in the United States District Court for the District of Delaware. TVS alleged that it had entered into a contractual relationship with Henogen SA, or Henogen, in 2010 with respect to the production of lentiviral vector vaccines for TVS. Henogen is a contract manufacturing organization with which we contracted for the manufacture of our LV305 product candidate. TVS alleged that its contractual relationship with Henogen contained an exclusivity provision limiting Henogen’s ability to participate in the manufacturing process of a vaccine based on lentiviral DNA vectors for third parties, as well as a provision preventing Henogen from sharing or using certain TVS confidential technology for manufacturing processes developed by TVS with or for the benefit of others. TVS alleged that we entered into a contractual relationship with Henogen in 2012 to manufacture lentiviral vectors for vaccines, which TVS contends interfered with its contract with Henogen and resulted in the use of certain TVS confidential information and trade secrets. The complaint asserted three counts for relief: tortious interference with contractual relationship, unfair competition and misappropriation of trade secrets. TVS did not specify its claimed damages, other than to assert that they exceed $75,000. TVS also requested in its complaint injunctive relief enjoining us from importing, receiving, possessing or using lentiviral vector vaccines developed or produced by Henogen, but never filed a motion seeking injunctive relief. The parties entered into several stipulations extending the deadline for us to respond to the complaint. On or about April 7, 2014, TVS filed a Notice of Voluntary Dismissal without prejudice of this lawsuit.

On or about July 24, 2014, shortly after our Registration Statement on Form S-1 was declared effective by the SEC for our initial public offering, TVS filed a new complaint against us in the Chancery Court of the State of Delaware, alleging facts substantially similar to the prior complaint. In addition, the complaint further alleges that we obtained shipments of lentiviral vectors for vaccines from Henogen and are conducting clinical trials with these lentiviral vectors. The complaint asserts four counts for relief: tortious interference with contractual relationship, unfair competition, misappropriation of trade secrets, and unjust enrichment; claimed damages were not specified. The complaint also requested injunctive relief enjoining us from using lentiviral vectors developed or produced by Henogen, using any other materials or information obtained by Henogen, and citing to the FDA or otherwise relying on any clinical trials using lentiviral vector vaccines developed or produced by Henogen.

On or about July 24, 2014, TVS also filed a motion for expedited proceedings in support of an anticipated motion for preliminary injunction. On August 8, 2014 the court granted TVS’ motion for expedited proceedings and set a hearing date in mid-November 2014 for TVS’ anticipated motion for preliminary injunction. In September 2014, TVS filed a motion to postpone the hearing date and delay the proceedings it previously sought to expedite. The court granted the motion and set a new date for the hearing. On or about December 15, 2014, TVS filed a motion for a preliminary injunction seeking, among other things, to enjoin us from making any use of lentiviral vectors pending final resolution of the litigation. A hearing was held on TVS’s motion in January 2015.

By order dated March 9, 2015, the Chancery Court denied TVS’ motion for a preliminary injunction. The court has not yet made any final determination on the merits of the lawsuit, which will be determined at a full trial. A trial date has not yet been set. On September 29 and 30, 2015, TVS and we participated in a voluntary non-binding mediation. However, to date we have not reached any agreement with TVS to settle this lawsuit and we may not be able to resolve the matter through mediation, in which case we intend to continue to vigorously defend this lawsuit. Due to the nature of the litigation and developments to date, we view a potential loss arising from this matter as reasonably possible. However, due to unresolved questions and issues that are critical to achieving settlement of this matter, if any, we cannot make a reasonable estimate of a potential loss, or range of loss, at this time.