Recently Issued Accounting Standards (Details) (USD $) In Millions, unless otherwise specified	6 Months Ended
Jun. 30, 2011 Integer
Collaboration Agreement with Sanofi-Aventis [Member]
Revenue Recognition, Milestone Method [Line Items]
Description of the overall arrangement	jointly develop and commercialize ZALTRAPTM (aflibercept, also known as VEGF Trap)
Description of milestone	substantive milestone payments upon receipt of specified marketing approvals
Maximum amount of substantive milestone payments that may be received	$ 400
Maximum amount of substantive milestone payments that may be received relating to marketing approvals in the U.S. or European Union	360
Maximum number of product candidates for which substantive milestone payments may be received relating to marketing approvals in the U.S. or European Union	8
Maximum amount of substantive milestone payments that may be received relating to marketing approvals in Japan	40
Maximum number of product candidates for which substantive milestone payments may be received relating to marketing approvals in Japan	5
The amount of substantive milestone payment to be made by the collaborating company to the entity, under certain defined circumstances.	10
Collaboration Agreement with Bayer HealthCare LLC [Member]
Revenue Recognition, Milestone Method [Line Items]
Description of the overall arrangement	globally develop, and commercialize outside the U.S., the Company's VEGF Trap for the treatment of eye disease by local administration EYLEATM
Description of milestone	substantive milestone payments related to marketing approvals of EYLEATM in major market countries outside the US
The amount of substantive milestone payment to be made by the collaborating company to the entity, under certain defined circumstances.	$ 50

The maximum amount in substantive milestone payments the Company may receive under the collaboration agreement.

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The maximum amount in substantive milestone payments the Company may receive under the collaboration agreement for product candidates in the U.S. or the European Union.

+ Details

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The maximum number of product candidates for which substantive milestone payments may be received in Japan, under the Company's collaboration agreement.

+ Details

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The maximum number of product candidates for which substantive milestone payments may be received in the U.S. or European Union, under the Company's collaboration agreement.

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The amount of substantive milestone payment to be made by the collaborating company to the entity, under certain defined circumstances.

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- Definition

A description of the overall arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 605
-SubTopic 28
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6891994&loc=SL6892177-166501

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

A description of each milestone and related contingent consideration as well as a description of whether or not each milestone(s) is considered substantive.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 605
-SubTopic 28
-Section 50
-Paragraph 2
-Subparagraph (b,c)
-URI http://asc.fasb.org/extlink&oid=6891994&loc=SL6892177-166501

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