BENEFIT PLANS (Components of Net Periodic Benefit Cost - Pension Benefits) (Details) - Pension Plans, Defined Benefit [Member] - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Components of Net Periodic Benefit Cost
Service cost	$ 1,194	$ 1,331	$ 2,387	$ 2,662
Interest cost	4,880	7,531	9,759	15,062
Expected return on plan assets	(11,375)	(12,485)	(22,750)	(24,969)
Amortization of prior service cost	336	335	673	670
Amortization of actuarial loss	2,179	3,140	4,357	6,279
Net periodic benefit credit	(2,786)	(148)	(5,574)	(296)
Pretax reclassification from AOCI included in net periodic pension benefit cost	$ 2,515	$ 3,475	$ 5,030	$ 6,949