BENEFIT PLANS (Components of Net Periodic Benefit Cost- Pension Plans) (Details) - Pension Benefits [Member] - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Components of Net Periodic Benefit Cost
Service cost	$ 1,654	$ 1,336
Interest cost	9,057	9,126
Expected return on plan assets	(12,096)	(12,891)
Amortization of prior service cost (credit)	335	(11)
Amortization of actuarial (gain) loss	1,824	1,541
Net periodic benefit cost (credit)	774	(899)
Pretax reclassification from AOCI included in net periodic pension/postretirement benefit cost (credit)	$ 2,159	$ 1,530