Stock-Based Compensation (Stock-Based Compensation Expense) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Schedule of stock-based compensation expense
Stock-based compensation	$ 626	$ 1,466	$ 3,361	$ 4,543
Research and development [Member]
Schedule of stock-based compensation expense
Stock-based compensation	97	682	989	2,183
Selling, general and administrative [Member]
Schedule of stock-based compensation expense
Stock-based compensation	529	784	2,372	2,360
Stock options [Member]
Schedule of stock-based compensation expense
Stock-based compensation	397	900	1,538	3,255
Restricted stock units [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period			843,698
Schedule of stock-based compensation expense
Stock-based compensation	527	566	1,823	1,288
Performance stock units [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period			523,048
Schedule of stock-based compensation expense
Stock-based compensation	$ (298)	$ 0	$ 0	$ 0