Allocation of Personnel Expenses - Allocation of Personnel Expenses by Function (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Condensed Income Statements, Captions [Line Items]
Personnel expenses	$ (332,353)	$ (246,171)	$ (189,418)
Research and Development Expense
Condensed Income Statements, Captions [Line Items]
Personnel expenses	(86,389)	(58,075)	(40,075)
Sales And Operations Expense
Condensed Income Statements, Captions [Line Items]
Personnel expenses	(185,065)	(150,426)	(119,609)
General and Administrative Expense
Condensed Income Statements, Captions [Line Items]
Personnel expenses	$ (60,899)	$ (37,670)	$ (29,734)