Stock-Based Compensation (Employee Stock-Based Compensation Expense) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Employee Stock Based Compensation Expense
Stock-based compensation expense (in dollars)	$ 4,847	$ 3,951	$ 9,389	$ 8,127
Cost of product revenues
Employee Stock Based Compensation Expense
Stock-based compensation expense (in dollars)	152	137	312	272
Research and development expense.
Employee Stock Based Compensation Expense
Stock-based compensation expense (in dollars)	1,269	1,113	2,522	2,153
Selling and marketing
Employee Stock Based Compensation Expense
Stock-based compensation expense (in dollars)	1,437	1,192	2,875	2,274
General and administrative
Employee Stock Based Compensation Expense
Stock-based compensation expense (in dollars)	$ 1,989	$ 1,509	$ 3,680	$ 3,428