EMPLOYEE BENEFITS (Details 4) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Pension Plan [Member]
Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax [Abstract]
Net (gain) loss arising during period	$ (5,821)	$ 5,794	$ 9,543
Amortization of transition asset	0	253	258
Amortization of prior service credit	311	311	318
Amortization of (loss)	(3,858)	(4,317)	(3,289)
Foreign currency exchange impact	1,619	(1,267)	(835)
Total recognized in other Comprehensive (income) loss	(7,749)	774	5,995
Net recognized in net periodic benefit cost and other comprehensive (income) loss	(4,742)	4,304	8,017
Other Postretirement Benefits Plan [Member]
Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax [Abstract]
Net (gain) loss arising during period	(15)	67	(100)
Amortization of transition asset	0	0	0
Amortization of prior service credit	0	0	0
Amortization of (loss)	43	58	51
Foreign currency exchange impact	0	0	0
Total recognized in other Comprehensive (income) loss	28	125	(49)
Net recognized in net periodic benefit cost and other comprehensive (income) loss	$ 70	$ 154	$ (14)