Quarterly Results of Operations - Textual (Details) - USD ($)	3 Months Ended		12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Business Acquisition, Contingent Consideration [Line Items]
Foreign exchange loss	$ (9,531)	$ (8,066)	$ 39,328,000	$ 18,482,000	$ 5,516,000
Stock-based compensation	4,771	5,463	17,796,000	17,696,000	22,438,000
Contingent Payment [Member]
Business Acquisition, Contingent Consideration [Line Items]
Business Combination, Contingent Consideration Arrangements, Change in Amount of Contingent Consideration, Liability	$ 41,910	$ 1,751	$ 36,344,000	$ 16,467,000	$ 35,914,000