Collaboration and License Agreements (Details Textual) In Millions, except Share data, unless otherwise specified								1 Months Ended	9 Months Ended	28 Months Ended				1 Months Ended	9 Months Ended
	Sep. 30, 2012 USD ($)	Jun. 30, 2012 USD ($)	Dec. 31, 2011 USD ($)	Sep. 30, 2012 November 30, 2011 exchange rate [Member] EUR (€)	Nov. 30, 2011 November 30, 2011 exchange rate [Member] USD ($)	Sep. 30, 2012 September 30 2012 Exchange Rate [Member] USD ($)	Sep. 30, 2012 September 30 2012 Exchange Rate [Member] EUR (€)	Feb. 29, 2008 Merck KGaA [Member] USD ($)	Sep. 30, 2012 Merck KGaA [Member] USD ($) Installment	Jun. 30, 2010 Merck KGaA [Member]	Nov. 30, 2011 Merck KGaA [Member] EUR (€)	Sep. 30, 2012 Merck KGaA [Member] September 30 2012 Exchange Rate [Member] USD ($)	Sep. 30, 2012 Merck KGaA [Member] September 30 2012 Exchange Rate [Member] EUR (€)	Dec. 31, 2006 Merck Sharp [Member] USD ($)	Sep. 30, 2012 Merck Sharp [Member] USD ($)
Collaboration And License Agreements (Textual) [Abstract]
License fee paid to company								$ 40.0						$ 20.0
License fee received after foreign currency exchange rate in effect by company								39.7
Period of upfront payment revenue recognition										28 months
Cumulative milestone revenue recognized in relation to the initiation of clinical trials or the achievement of preclinical milestones									12.1						1.0
Maximum reimbursement agreed by the company				1.8	2.4				2.3		1.8	2.3	1.8
Payable termination agreement reimbursement						1.3	1.0
Amount agreed to pay by the company on achievement of milestones						1.3	1.0
Number of monthly installments									10
Final monthly installment									1
Revenue Recognition Period														4 years
Extended revenue recognition period														2 years
Proceeds from the sale of common stock under Stock Purchase Agreement														10.0
Common stock price per share	$ 1.03	$ 1.06	$ 1.05											$ 5.50
Aggregate potential milestones to be received under collaboration - one															165.0
Aggregate potential milestones to be received under collaboration - two															$ 260.0
Stock issued during period														1,818,182