OTHER NONOPERATING EXPENSE, NET (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Other Income and Expenses [Abstract]
Interest income	$ 90	$ 109	$ 483	$ 339
Foreign currency exchange gain / (loss), net	630	(568)	13,050	(9,768)
Change in fair value of derivatives (Note 11)	(398)	(2,443)	(11,904)	(5,673)
Other income / (expense), net	65	(3,575)	7	(7,020)
Total other non-operating income / (expense)	$ 387	$ (6,477)	$ 1,636	$ (22,122)