ACCUMULATED OTHER COMPREHENSIVE INCOME/(LOSS) (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
Accumulated other comprehensive income activity
Balance at the beginning of the period	$ 1,149,411
Balance at the end of the period	1,258,298
Foreign Currency
Accumulated other comprehensive income activity
Balance at the beginning of the period	(206,725)	$ (42,851)
Other comprehensive income (loss) before reclassifications	30,454	(94,147)
Net current-period other comprehensive income (loss)	30,454	(94,147)
Balance at the end of the period	(176,271)	(136,998)
Defined Benefit Pension Plans
Accumulated other comprehensive income activity
Balance at the beginning of the period	(55,550)	(67,097)
Amounts reclassified from accumulated other comprehensive income	1,674	2,342
Net current-period other comprehensive income (loss)	1,674	2,342
Balance at the end of the period	(53,876)	(64,755)
Other
Accumulated other comprehensive income activity
Balance at the beginning of the period	(72)	(97)
Amounts reclassified from accumulated other comprehensive income	13	13
Net current-period other comprehensive income (loss)	13	13
Balance at the end of the period	(59)	(84)
Accumulated Other Comprehensive Income/(Loss)
Accumulated other comprehensive income activity
Balance at the beginning of the period	(262,347)	(110,045)
Other comprehensive income (loss) before reclassifications	30,454	(94,147)
Amounts reclassified from accumulated other comprehensive income	1,687	2,355
Net current-period other comprehensive income (loss)	32,141	(91,792)
Balance at the end of the period	$ (230,206)	$ (201,837)