Collaboration Agreements (EYLEA) (Details) (USD $)	3 Months Ended	9 Months Ended	3 Months Ended					9 Months Ended		3 Months Ended
	Sep. 30, 2014	Sep. 30, 2014	Mar. 31, 2014 sales achievement - $500 million	Mar. 31, 2014 sales achievement - $600 million	Jun. 30, 2014 sales achievement - 700 million	Sep. 30, 2014 sales achievement - $800 million	Sep. 30, 2014 sales achievement - $900 million	Sep. 30, 2014 sales achievement - $1 billion	Sep. 30, 2014 sales achievement - $200 million	Mar. 31, 2014 BRVO
Collaboration Agreement [Line Items]
Number of sales milestone payments the Company received	2	5
Revenue Recognition, Milestone Method, Revenue Recognized			$ 15,000,000	$ 15,000,000	$ 15,000,000	$ 15,000,000	$ 15,000,000
Levels of twelve month sales at which sales milestone payments were received - 500 million		500,000,000
Levels of twelve month sales at which sales milestone payments were received - 600 million		600,000,000
Levels of twelve month sales at which sales milestone payments were received - 700 million		700,000,000
Levels of twelve month sales at which sales milestone payments were received - 800 million	800,000,000
Levels of twelve month sales at which sales milestone payments were received - 900 million	900,000,000
Period for Achieving Sales Target for Milestone Payment, Rolling Basis		12 months
Number of sales milestone payments the Company might receive								1
levels of twelve months sales at which sales milestone payments maybe received - 1 billion		1,000,000,000
Maximum amount of sales milestone payments if total sales achieve specific levels								15,000,000	30,000,000
levels of twelve month sales at which sales milestone payments maybe received - 200 million		200,000,000
Reimbursement of Regeneron research and development expenses										$ 15,700,000