Share-Based Payments - Schedule of Stock-Based Compensation Expense by Award Type Included Within the Condensed Consolidated Statements of Operations (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	$ 20,430	$ 18,547	$ 40,120	$ 36,655
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	11,503	12,467	23,106	25,513
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	7,780	5,243	13,912	9,791
Performance-Based Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	478	0	1,866	186
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	399	392	696	720
Other Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	$ 270	$ 445	$ 540	$ 445