ACCUMULATED OTHER COMPREHENSIVE INCOME/(LOSS) (Details) - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Sep. 30, 2023	Sep. 30, 2022
AOCI Attributable to Parent [Roll Forward]
OCI Before Reclassifications							$ 100	$ (4,500)
Amounts Reclassified from AOCI							15,300	5,800
Other Comprehensive Income, Net of Tax	$ 8,081	$ 4,088	$ 3,230	$ 1,858	$ (1,293)	$ 704	15,399	1,269
Accumulated Other Comprehensive Loss
AOCI Attributable to Parent [Roll Forward]
Balance as of Beginning of Period			(39,400)			(42,300)	(39,400)	(42,300)
Other Comprehensive Income, Net of Tax	8,081	$ 4,088	3,230	1,858	$ (1,293)	704
Balance as of End of Period	(24,000)			(41,000)			(24,000)	(41,000)
Qualified Cash Flow Hedging Instruments
AOCI Attributable to Parent [Roll Forward]
Balance as of Beginning of Period			(400)			(400)	(400)	(400)
OCI Before Reclassifications							0	0
Amounts Reclassified from AOCI							0	0
Other Comprehensive Income, Net of Tax							0	0
Balance as of End of Period	(400)			(400)			(400)	(400)
Unrealized Gains/(Losses) on Marketable Securities
AOCI Attributable to Parent [Roll Forward]
Balance as of Beginning of Period			(1,200)			400	(1,200)	400
OCI Before Reclassifications							0	(2,000)
Amounts Reclassified from AOCI							1,200	0
Other Comprehensive Income, Net of Tax							1,200	(2,000)
Balance as of End of Period	0			(1,600)			0	(1,600)
Defined Benefit Plans
AOCI Attributable to Parent [Roll Forward]
Balance as of Beginning of Period			$ (37,800)			$ (42,300)	(37,800)	(42,300)
OCI Before Reclassifications							100	(2,500)
Amounts Reclassified from AOCI							14,100	5,800
Other Comprehensive Income, Net of Tax							14,200	3,300
Balance as of End of Period	$ (23,600)			$ (39,000)			$ (23,600)	$ (39,000)