BENEFIT PLANS (Components of Net Periodic Benefit Cost- Other Postretirement Benefits) (Details) - Other Postretirement Benefit 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	$ 265	$ 380	$ 530	$ 760
Interest cost	106	242	212	485
Amortization of prior service credit	(477)	(980)	(953)	(1,959)
Amortization of actuarial gain	(367)	(201)	(734)	(403)
Net periodic benefit credit	(473)	(559)	(945)	(1,117)
Pretax reclassifications from AOCI included in net periodic postretirement benefit credit	$ (844)	$ (1,181)	$ (1,687)	$ (2,362)