Savings Plans, Pension Plans and Other Postretirement Employee Benefits (Amounts Recorded in AOCI on Consolidated Balance Sheets, Not Recognized as Components of Net Periodic Benefit Costs) (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Pension Plans [Member]
Net (loss) income	$ (33,043)	$ (49,476)
Prior service (cost) credit	(49)	(103)
Total amount unrecognized	(33,092)	(49,579)
OPEB [Member]
Net (loss) income	4,598	(2,075)
Prior service (cost) credit	0	285
Total amount unrecognized	$ 4,598	$ (1,790)