Legal Matters	9 Months Ended
Sep. 30, 2013
Commitments and Contingencies Disclosure [Abstract]
Legal Matters	Legal Matters From time to time, the Company is a party to legal proceedings in the course of the Company’s business. The Company does not expect any such current legal proceedings to have a material adverse effect on the Company’s business or financial condition. Costs associated with the Company’s involvement in legal proceedings are expensed as incurred. License and Settlement Agreements with Genentech On December 31, 2011, the Company entered into a Non-Exclusive License and Partial Settlement Agreement with Genentech (the "Original Genentech Agreement") that covered making, using, and selling EYLEA in the United States for the prevention and treatment of human eye diseases and disorders in the United States, and ended the litigation relating to those matters. Under the Original Genentech Agreement, the Company received a non-exclusive license to the Davis-Smyth patents, and certain other patents owned or co-owned by Genentech. The Original Genentech Agreement did not cover any non-U.S. patent rights or non-U.S. patent disputes, and did not cover any use of aflibercept other than for prevention and treatment of human eye diseases and disorders in the United States. The Original Genentech Agreement provided for the Company to make payments to Genentech based on U.S. sales of EYLEA through May 7, 2016, the date the Davis-Smyth patents expire. Under the Original Genentech Agreement, the Company made a $60.0 million payment when cumulative U.S. sales of EYLEA reached $400 million, and is obligated to pay royalties of 4.75% on cumulative relevant sales of EYLEA between $400 million and $3 billion and 5.5% on any cumulative relevant sales of EYLEA over $3 billion. Effective May 17, 2013, the Company entered into an Amended and Restated Non-Exclusive License and Settlement Agreement with Genentech (the "Amended Genentech Agreement"), which amended the Original Genentech Agreement to now include all sales of EYLEA worldwide and ended the litigation relating to those matters. Under the Amended Genentech Agreement, the Company received a worldwide non-exclusive license to the Davis-Smyth patents, and certain other patents, owned or co-owned by Genentech for the prevention or treatment of eye diseases and eye disorders in a human through administration of EYLEA to the eye. Under the Amended Genentech Agreement, the Company is obligated to make payments to Genentech based on sales of EYLEA in the United States, and EYLEA manufactured in the United States and sold outside the United States, through May 7, 2016 using the same milestone and royalty rates as in the Original Genentech Agreement. EYLEA is sold outside the United States by affiliates of Bayer HealthCare under the Company's license and collaboration agreement. All payments to Genentech under the Original Genentech Agreement and the Amended Genentech Agreement have been or will be made by the Company. Bayer HealthCare will share in all such payments based on the proportion of ex-U.S. EYLEA sales to worldwide EYLEA sales and determined consistent with the license and collaboration agreement. Also on May 17, 2013, the Company entered into a Non-Exclusive License and Settlement Agreement (the "ZALTRAP Agreement") with Genentech and Sanofi under which the Company and Sanofi received a worldwide non-exclusive license to the Davis-Smyth patents, and certain other patents, in all indications for human use other than the prevention or treatment of eye diseases and eye disorders through administration to the eye. Under the terms of the ZALTRAP Agreement, payments are required to be made to Genentech based on sales of ZALTRAP in the United States and of ZALTRAP that is manufactured in the United States and sold outside the United States through May 7, 2016. A payment of $19 million is required to be made upon cumulative relevant sales of ZALTRAP reaching $200 million. In addition, royalty payments are required to be made to Genentech based upon 4.5% of cumulative relevant sales of ZALTRAP between $400 million and $1 billion and 6.5% of any cumulative relevant sales of ZALTRAP over $1 billion. All payments to Genentech under the ZALTRAP Agreement will be made by Sanofi, and the Company will share in all such payments.

Legal Matters

From time to time, the Company is a party to legal proceedings in the course of the Company’s business. The Company does not expect any such current legal proceedings to have a material adverse effect on the Company’s business or financial condition. Costs associated with the Company’s involvement in legal proceedings are expensed as incurred.

License and Settlement Agreements with Genentech

On December 31, 2011, the Company entered into a Non-Exclusive License and Partial Settlement Agreement with Genentech (the "Original Genentech Agreement") that covered making, using, and selling EYLEA in the United States for the prevention and treatment of human eye diseases and disorders in the United States, and ended the litigation relating to those matters. Under the Original Genentech Agreement, the Company received a non-exclusive license to the Davis-Smyth patents, and certain other patents owned or co-owned by Genentech. The Original Genentech Agreement did not cover any non-U.S. patent rights or non-U.S. patent disputes, and did not cover any use of aflibercept other than for prevention and treatment of human eye diseases and disorders in the United States. The Original Genentech Agreement provided for the Company to make payments to Genentech based on U.S. sales of EYLEA through May 7, 2016, the date the Davis-Smyth patents expire. Under the Original Genentech Agreement, the Company made a $60.0 million payment when cumulative U.S. sales of EYLEA reached $400 million, and is obligated to pay royalties of 4.75% on cumulative relevant sales of EYLEA between $400 million and $3 billion and 5.5% on any cumulative relevant sales of EYLEA over $3 billion.

Effective May 17, 2013, the Company entered into an Amended and Restated Non-Exclusive License and Settlement Agreement with Genentech (the "Amended Genentech Agreement"), which amended the Original Genentech Agreement to now include all sales of EYLEA worldwide and ended the litigation relating to those matters. Under the Amended Genentech Agreement, the Company received a worldwide non-exclusive license to the Davis-Smyth patents, and certain other patents, owned or co-owned by Genentech for the prevention or treatment of eye diseases and eye disorders in a human through administration of EYLEA to the eye. Under the Amended Genentech Agreement, the Company is obligated to make payments to Genentech based on sales of EYLEA in the United States, and EYLEA manufactured in the United States and sold outside the United States, through May 7, 2016 using the same milestone and royalty rates as in the Original Genentech Agreement. EYLEA is sold outside the United States by affiliates of Bayer HealthCare under the Company's license and collaboration agreement. All payments to Genentech under the Original Genentech Agreement and the Amended Genentech Agreement have been or will be made by the Company. Bayer HealthCare will share in all such payments based on the proportion of ex-U.S. EYLEA sales to worldwide EYLEA sales and determined consistent with the license and collaboration agreement.

Also on May 17, 2013, the Company entered into a Non-Exclusive License and Settlement Agreement (the "ZALTRAP Agreement") with Genentech and Sanofi under which the Company and Sanofi received a worldwide non-exclusive license to the Davis-Smyth patents, and certain other patents, in all indications for human use other than the prevention or treatment of eye diseases and eye disorders through administration to the eye. Under the terms of the ZALTRAP Agreement, payments are required to be made to Genentech based on sales of ZALTRAP in the United States and of ZALTRAP that is manufactured in the United States and sold outside the United States through May 7, 2016. A payment of $19 million is required to be made upon cumulative relevant sales of ZALTRAP reaching $200 million. In addition, royalty payments are required to be made to Genentech based upon 4.5% of cumulative relevant sales of ZALTRAP between $400 million and $1 billion and 6.5% of any cumulative relevant sales of ZALTRAP over $1 billion. All payments to Genentech under the ZALTRAP Agreement will be made by Sanofi, and the Company will share in all such payments.