EMPLOYEE RETIREMENT PLANS - Assumptions Used to Determine Net Periodic Pension Cost (Details)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Assumptions used to determine the net periodic pension cost [Abstract]
Discount rate	3.22%	3.41%	3.57%
Rate of compensation increases	3.50%	3.50%	3.50%