Collaborations	3 Months Ended
Mar. 31, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Collaborations	6. Collaborations NMP License and Commercialization Agreement In August 2013, the Company entered into a license and commercialization agreement with Nihon Medi-Physic Co., LTD. (“NMP”) that grants NMP the right to develop and commercialize etarfolatide in Japan for use in connection with vintafolide in Japan. The Company received a $1.0 million non-refundable upfront payment, is eligible for up to $4.5 million based on the successful achievement of regulatory goals for etarfolatide in five different cancer indications and is eligible to receive double-digit percentage royalties on sales of etarfolatide in Japan. For revenue recognition purposes, the Company viewed the agreement with NMP as a multiple element arrangement. Multiple element arrangements are analyzed to determine whether the various performance obligations, or elements, can be separated or whether they must be accounted for as a single unit of accounting. The Company has identified the deliverables related to the collaboration with NMP, which include the license granted to NMP, as well as the obligation to provide pre-clinical and clinical supply of etarfolatide, to provide rights to NMP if a product is developed that replaces etarfolatide, the obligation for the Company to provide clinical data to NMP during the contract period and the coordination of development and commercialization efforts between the Company for vintafolide and NMP for etarfolatide in Japan. The Company’s deliverables will be accounted for as a single unit of account, therefore the non-refundable upfront payment is being recognized on a straight-line basis over the performance period. This determination was made because the successful development of etarfolatide in Japan requires the ongoing participation by the Company, including the development of the related therapeutic drug, vintafolide. The performance period over which the revenue will be recognized continues from the date of execution of the agreement through the end of 2033, the estimated termination date of the contract which is when the Company’s performance obligations will be completed. Any significant changes in the timing of the performance period could result in a change in the revenue recognition period. The Company had deferred revenue related to the agreement of approximately $0.8 million at March 31, 2017. Subsequent to the inception of the NMP arrangement, the Company evaluates the remaining deliverables for separation as items in the arrangement are delivered. The arrangement with NMP includes milestone payments of up to approximately $4.5 million and the milestones are based on the commencement of clinical trials in Japan for specific and non-specific indications and filing for approval in Japan for specific and non-specific indications. The Company evaluated each of these milestone payments and believes that all of the milestones are substantive as there is substantial performance risk that must occur in order for them to be met because the Company must complete additional clinical trials which show a positive outcome or receive approval from a regulatory authority and would be commensurate with the enhancement of value of the underlying intellectual property. To date, the products have not been approved in Japan and no revenue has been recognized related to the regulatory milestones or royalties as continued development of vintafolide is still an opportunity that the Company could pursue in the future. NMP has the right to terminate the collaboration agreement on 90 days notice prior to the first commercial sale in Japan and six months notice after the first commercial sale in Japan. NMP also has the right to terminate the agreement on six months notice if the Company fails to launch vintafolide after receiving regulatory approval in Japan. NMP and the Company each have the right to terminate the agreement due to the material breach or insolvency of the other party. Upon termination of the agreement depending on the circumstances, the parties have varying rights and obligations with respect to licensing and related regulatory materials and data.

6. Collaborations

NMP License and Commercialization Agreement

In August 2013, the Company entered into a license and commercialization agreement with Nihon Medi-Physic Co., LTD. (“NMP”) that grants NMP the right to develop and commercialize etarfolatide in Japan for use in connection with vintafolide in Japan. The Company received a $1.0 million non-refundable upfront payment, is eligible for up to $4.5 million based on the successful achievement of regulatory goals for etarfolatide in five different cancer indications and is eligible to receive double-digit percentage royalties on sales of etarfolatide in Japan.

For revenue recognition purposes, the Company viewed the agreement with NMP as a multiple element arrangement. Multiple element arrangements are analyzed to determine whether the various performance obligations, or elements, can be separated or whether they must be accounted for as a single unit of accounting. The Company has identified the deliverables related to the collaboration with NMP, which include the license granted to NMP, as well as the obligation to provide pre-clinical and clinical supply of etarfolatide, to provide rights to NMP if a product is developed that replaces etarfolatide, the obligation for the Company to provide clinical data to NMP during the contract period and the coordination of development and commercialization efforts between the Company for vintafolide and NMP for etarfolatide in Japan. The Company’s deliverables will be accounted for as a single unit of account, therefore the non-refundable upfront payment is being recognized on a straight-line basis over the performance period. This determination was made because the successful development of etarfolatide in Japan requires the ongoing participation by the Company, including the development of the related therapeutic drug, vintafolide. The performance period over which the revenue will be recognized continues from the date of execution of the agreement through the end of 2033, the estimated termination date of the contract which is when the Company’s performance obligations will be completed. Any significant changes in the timing of the performance period could result in a change in the revenue recognition period. The Company had deferred revenue related to the agreement of approximately $0.8 million at March 31, 2017. Subsequent to the inception of the NMP arrangement, the Company evaluates the remaining deliverables for separation as items in the arrangement are delivered.

The arrangement with NMP includes milestone payments of up to approximately $4.5 million and the milestones are based on the commencement of clinical trials in Japan for specific and non-specific indications and filing for approval in Japan for specific and non-specific indications. The Company evaluated each of these milestone payments and believes that all of the milestones are substantive as there is substantial performance risk that must occur in order for them to be met because the Company must complete additional clinical trials which show a positive outcome or receive approval from a regulatory authority and would be commensurate with the enhancement of value of the underlying intellectual property. To date, the products have not been approved in Japan and no revenue has been recognized related to the regulatory milestones or royalties as continued development of vintafolide is still an opportunity that the Company could pursue in the future.

NMP has the right to terminate the collaboration agreement on 90 days notice prior to the first commercial sale in Japan and six months notice after the first commercial sale in Japan. NMP also has the right to terminate the agreement on six months notice if the Company fails to launch vintafolide after receiving regulatory approval in Japan. NMP and the Company each have the right to terminate the agreement due to the material breach or insolvency of the other party. Upon termination of the agreement depending on the circumstances, the parties have varying rights and obligations with respect to licensing and related regulatory materials and data.