EMPLOYEE BENEFIT PLANS - Net Periodic Costs and Other Amounts Recognized (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Components of Net Periodic Cost and Other Amounts Recognized in other Comprehensive Income, Net periodic pension cost:
Service cost	$ 64	$ 560	$ 638
Interest cost	757	859	770
Expected return on plan assets	(983)	(1,153)	(985)
Amortization of prior service cost	0	0	25
Amortization of unrecognized net loss	159	209	479
Net periodic benefit cost	$ (3)	$ 475	$ 927