OTHER NONOPERATING EXPENSE, NET (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Other Income and Expenses [Abstract]
Interest income	$ 285	$ 118	$ 393	$ 230
Foreign currency exchange (loss) / gain, net	(3,002)	2,289	12,420	(9,200)
Change in fair value of derivatives (Note 11)	2,544	(2,220)	(11,506)	(3,230)
Other income / (expense), net	6	(3,091)	(58)	(3,445)
Total other non-operating (expense) / income	$ (167)	$ (2,904)	$ 1,249	$ (15,645)