Employee Benefits and Share-Based Compensation - Shared-based Compensation Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total share-based compensation expense	$ 28,885	$ 21,857	$ 19,500
Cost of product and service revenues
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total share-based compensation expense	4,634	3,478	2,596
Research and development
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total share-based compensation expense	5,746	3,590	3,128
Selling, general and administrative
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total share-based compensation expense	18,505	14,789	13,776
2009 Plan
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Income tax benefit	$ 6,500	$ 8,200	$ 5,400