Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Statement of Comprehensive Income [Abstract]
NET INCOME	$ 93,999	$ 93,004	$ 113,992
OTHER COMPREHENSIVE INCOME (LOSS):
Foreign Currency Transaction Gain (Loss), Unrealized	(54,457)	(27,426)
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Reclassification Adjustment from AOCI, Realized upon Sale or Liquidation, Net of Tax	0	1,178	0
Net unrealized loss on foreign currency translation	(54,457)	(26,248)	(31,701)
Unrealized gain (loss) on interest rate swaps:
Unrealized gain (loss) arising during the period, net of tax benefit	(9,856)	(11,153)	6,112
Reclassification adjustment for loss included in interest expense, net of tax provision	8,313	7,094	6,969
Net unrealized gain (loss) on interest rate swaps, net of tax	(1,543)	(4,059)	13,081
OTHER COMPREHENSIVE INCOME (LOSS), NET OF TAXES	(56,000)	(30,307)	(18,620)
COMPREHENSIVE INCOME	$ 37,999	$ 62,697	$ 95,372