Equity-Based Compensation - Equity-Based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Equity-based compensation expense
Total equity-based compensation expense	$ 5,051	$ 5,641	$ 14,633	$ 15,378
Income tax effect	0	(1,674)	0	(4,569)
After-tax effect of equity-based compensation expense	5,051	3,967	14,633	10,809
Cost of product sales
Equity-based compensation expense
Total equity-based compensation expense	281	432	588	690
Research and development
Equity-based compensation expense
Total equity-based compensation expense	568	799	1,896	2,651
Selling, general and administrative
Equity-based compensation expense
Total equity-based compensation expense	$ 4,202	$ 4,410	$ 12,149	$ 12,037