Equity-Based Compensation (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Equity-based compensation expense
Total equity-based compensation expense	$ 1,665	$ 2,050	$ 5,886	$ 5,312
Cost of product sales
Equity-based compensation expense
Total equity-based compensation expense	25	52	83	198
Research and development
Equity-based compensation expense
Total equity-based compensation expense	337	473	1,634	1,420
Selling, general and administrative
Equity-based compensation expense
Total equity-based compensation expense	$ 1,303	$ 1,525	$ 4,169	$ 3,694