BENEFIT PLANS (Components of Net Periodic Benefit Cost- Other Postretirement Benefits) (Details) - Postretirement Benefits [Member] - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Components of Net Periodic Benefit Cost
Service cost	$ 380	$ 329
Interest cost	242	347
Amortization of prior service credit	(980)	(980)
Amortization of actuarial gain	(201)	(327)
Net periodic benefit cost (credit)	(559)	(631)
Pretax reclassifications from AOCI included in net periodic postretirement benefit credit	$ (1,181)	$ (1,307)