EMPLOYEE BENEFIT PLANS - Changes in Benefit Obligations and Plan Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
EMPLOYEE BENEFIT PLANS [Abstract]
Defined Benefit Plan, Type [Extensible List]	us-gaap:DefinedBenefitPostretirementHealthCoverageMember
Defined Benefit Plan, Funding Status [Extensible List]	us-gaap:UnfundedPlanMember
Change in benefit obligation [Roll Forward]
Benefit obligation at beginning of period	$ 1,411	$ 958
Initial adoption of new plan	0	444
Service cost with interest to end of year	67	66	$ 54
Interest cost	46	48	36
Participant contributions	28	5
Benefits paid	(58)	(9)
Actuarial (gain)/loss	78	(101)
Benefit obligation at end of period	1,573	1,411	958
Change in plan assets [Roll Forward]
Fair value of plan assets at beginning of year	0	0
Employer (reimbursement)/contributions	30	4
Participant contributions	28	5
Benefits paid	(58)	(9)
Fair value of plan assets at end of year	$ 0	$ 0	$ 0