BENEFIT PLANS (Components of Net Periodic Benefit Cost - Pension Benefits) (Details) - Pension Plans, Defined Benefit [Member] - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Components of Net Periodic Benefit Cost
Service cost	$ 1,193	$ 1,331
Interest cost	4,879	7,531
Expected return on plan assets	(11,375)	(12,485)
Amortization of prior service cost	337	335
Amortization of actuarial loss	2,178	3,140
Net periodic benefit credit	(2,788)	(148)
Pretax reclassification from AOCI included in net periodic pension benefit cost	$ 2,515	$ 3,475