EMPLOYEE BENEFIT PLANS - Net Periodic Pension Cost (Credit) (Details) - Defined Benefit Pension Plan - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 0	$ 24
Interest cost	593	601
Expected return on plan assets	(607)	(970)
Amortization of net actuarial loss	8	0
Net periodic pension credit	$ (6)	$ (345)