Collaboration Agreement	12 Months Ended
Dec. 31, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Collaboration Agreement	Collaboration Agreement On May 28, 2013, the Company entered into the collaboration and license agreement (the "Collaboration and License Agreement") with ThromboGenics N.V. ("ThromboGenics"). Under the Collaboration and License Agreement, the Company and ThromboGenics collaborated to seek to identify protein or peptide therapeutics that directly modulate any of a specified set of targets in a novel pathway in retinal disease. ThromboGenics funded certain research and development services performed by the Company during the research term, which was initially thirty (30) months and automatically extended to the extent that the parties mutually agreed in writing. The initial research term concluded in November 2015, however it was amended at that time to extend the performance period into 2016. The Collaboration and License Agreement provided for potential future payments to the Company upon achievement of specified pre-clinical, clinical and regulatory milestones with respect to collaboration products and royalties on sales of collaboration products by ThromboGenics, its affiliates or sublicensees. However, as there have not been any collaboration products identified whose modulation of any of the targets has been confirmed in the course of the research conducted under the Collaboration and License Agreement, none of these milestones or royalties were payable. On August 1, 2016, the Company received notice from ThromboGenics of its termination, effective as of October 31, 2016, of the Collaboration and License Agreement. The Company accounted for this agreement pursuant to ASC Topic 605-25. The Company received a $1.75 million upfront payment and subsequent payments to perform activities under the Collaboration and License Agreement at a set rate per full-time equivalent person working on collaboration activities. The Company was recognizing the arrangement consideration using the proportional performance method, by which the amounts were recognized in proportion to the costs incurred based on full time equivalent personnel efforts. Subsequent to the amendment in November 2015, the Company was recognizing revenue on a straight-line basis over the remaining performance period. The Company recorded revenue of $0.4 million, $0.5 million and $2.2 million for the years ended December 31, 2016, 2015 and 2014, respectively. No further amounts are expected to be recognized in the future related to this arrangement. The costs incurred by the Company related to the research activities were recorded as research and development expense in the consolidated statement of operations and comprehensive income (loss).

Collaboration Agreement

On May 28, 2013, the Company entered into the collaboration and license agreement (the "Collaboration and License Agreement") with ThromboGenics N.V. ("ThromboGenics"). Under the Collaboration and License Agreement, the Company and ThromboGenics collaborated to seek to identify protein or peptide therapeutics that directly modulate any of a specified set of targets in a novel pathway in retinal disease.

ThromboGenics funded certain research and development services performed by the Company during the research term, which was initially thirty (30) months and automatically extended to the extent that the parties mutually agreed in writing. The initial research term concluded in November 2015, however it was amended at that time to extend the performance period into 2016. The Collaboration and License Agreement provided for potential future payments to the Company upon achievement of specified pre-clinical, clinical and regulatory milestones with respect to collaboration products and royalties on sales of collaboration products by ThromboGenics, its affiliates or sublicensees. However, as there have not been any collaboration products identified whose modulation of any of the targets has been confirmed in the course of the research conducted under the Collaboration and License Agreement, none of these milestones or royalties were payable. On August 1, 2016, the Company received notice from ThromboGenics of its termination, effective as of October 31, 2016, of the Collaboration and License Agreement.

The Company accounted for this agreement pursuant to ASC Topic 605-25. The Company received a $1.75 million upfront payment and subsequent payments to perform activities under the Collaboration and License Agreement at a set rate per full-time equivalent person working on collaboration activities. The Company was recognizing the arrangement consideration using the proportional performance method, by which the amounts were recognized in proportion to the costs incurred based on full time equivalent personnel efforts. Subsequent to the amendment in November 2015, the Company was recognizing revenue on a straight-line basis over the remaining performance period. The Company recorded revenue of $0.4 million, $0.5 million and $2.2 million for the years ended December 31, 2016, 2015 and 2014, respectively. No further amounts are expected to be recognized in the future related to this arrangement. The costs incurred by the Company related to the research activities were recorded as research and development expense in the consolidated statement of operations and comprehensive income (loss).