Concentration of Credit Risk (Details)	3 Months Ended													12 Months Ended	3 Months Ended	12 Months Ended
	Mar. 31, 2013 Total Contract Revenues Customer Concentration Collaboration Partner A	Mar. 31, 2012 Total Contract Revenues Customer Concentration Collaboration Partner A	Mar. 31, 2013 Total Contract Revenues Customer Concentration Collaboration Partner B	Mar. 31, 2012 Total Contract Revenues Customer Concentration Collaboration Partner B	Mar. 31, 2013 Total Net Product Revenues Customer Concentration Customer A	Mar. 31, 2012 Total Net Product Revenues Customer Concentration Customer A	Mar. 31, 2013 Total Net Product Revenues Customer Concentration Customer B	Mar. 31, 2012 Total Net Product Revenues Customer Concentration Customer B	Mar. 31, 2013 Total Net Product Revenues Customer Concentration Customer C	Mar. 31, 2012 Total Net Product Revenues Customer Concentration Customer C	Mar. 31, 2013 Total Net Product Revenues Customer Concentration Customer D	Mar. 31, 2012 Total Net Product Revenues Customer Concentration Customer D	Mar. 31, 2013 Accounts receivable Credit Concentration Collaboration Partner A and Collaboration Partner B	Dec. 31, 2012 Accounts receivable Credit Concentration Collaboration Partner A and Collaboration Partner B	Mar. 31, 2013 Accounts receivable Credit Concentration Customer A, B, C and D	Dec. 31, 2012 Accounts receivable Credit Concentration Customer A, B, C and D
Concentration of risk
Percentage of concentration risk	60.00%	60.00%	40.00%	40.00%	27.00%	33.00%	18.00%	26.00%	12.00%	16.00%	12.00%	12.00%	24.00%	73.00%	54.00%	17.00%