EMPLOYEE BENEFITS (AOCI) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Unrecognized prior service cost	$ 0	$ 0
Unrecognized actuarial (gain) loss	60,571	49,745
Total amounts recognized in AOCI	60,571	49,745
Anticipated amortization of net actuarial losses in next fiscal year	4,287
Post-retirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Unrecognized prior service cost	(26,880)	(32,289)
Unrecognized actuarial (gain) loss	25,235	20,756
Total amounts recognized in AOCI	(1,645)	$ (11,533)
Anticipated amortization of net actuarial losses in next fiscal year	$ 2,355