ACCUMULATED OTHER COMPREHENSIVE INCOME/(LOSS) (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2023	Mar. 31, 2023	Jun. 30, 2022	Mar. 31, 2022	Jun. 30, 2023	Jun. 30, 2022
AOCI Attributable to Parent [Roll Forward]
OCI Before Reclassifications					$ 100	$ (3,800)
Amounts Reclassified from AOCI					7,200	3,200
Other Comprehensive Income (Loss), Net of Tax	$ 4,088	$ 3,230	$ (1,293)	$ 704	7,318	(589)
Accumulated Other Comprehensive Loss
AOCI Attributable to Parent [Roll Forward]
Beginning balance		(39,400)		(42,300)	(39,400)	(42,300)
Other Comprehensive Income (Loss), Net of Tax	4,088	3,230	(1,293)	704
Ending balance	(32,100)		(42,900)		(32,100)	(42,900)
Qualified Cash Flow Hedging Instruments
AOCI Attributable to Parent [Roll Forward]
Beginning balance		(400)		(400)	(400)	(400)
OCI Before Reclassifications					0	0
Amounts Reclassified from AOCI					0	0
Other Comprehensive Income (Loss), Net of Tax					0	0
Ending balance	(400)		(400)		(400)	(400)
Unrealized Gains/(Losses) on Marketable Securities
AOCI Attributable to Parent [Roll Forward]
Beginning balance		(1,200)		400	(1,200)	400
OCI Before Reclassifications					0	(1,300)
Amounts Reclassified from AOCI					1,200	0
Other Comprehensive Income (Loss), Net of Tax					1,200	(1,300)
Ending balance	0		(900)		0	(900)
Defined Benefit Plans
AOCI Attributable to Parent [Roll Forward]
Beginning balance		$ (37,800)		$ (42,300)	(37,800)	(42,300)
OCI Before Reclassifications					100	(2,500)
Amounts Reclassified from AOCI					6,000	3,200
Other Comprehensive Income (Loss), Net of Tax					6,100	700
Ending balance	$ (31,700)		$ (41,600)		$ (31,700)	$ (41,600)