Allocation of Personnel Expenses - Allocation of Personnel Expenses by Nature (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Compensation Related Costs [Abstract]
Wages and salaries	$ (220,317)	$ (170,079)	$ (128,737)
Severance pay	(2,726)	(1,343)	(2,469)
Social charges	(59,668)	(47,176)	(38,814)
Other social expenses	(9,913)	(6,033)	(3,178)
Acquisition-related deferred price consideration	(85)	(324)	(950)
Share based compensation	43,259	23,989	19,600
Profit sharing	(1,326)	(613)	(733)
Research tax credit	4,941	3,386	5,063
Personnel expenses	$ (332,353)	$ (246,171)	$ (189,418)