ACCUMULATED OTHER COMPREHENSIVE LOSS - Schedule of Accumulated Other Comprehensive Loss (Details) - USD ($)		3 Months Ended		9 Months Ended
		Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
BALANCE		$ 1,338,766,000	$ 1,165,309,000	$ 1,275,369,000	$ 1,099,914,000
Reclassification to net income				759,000	1,500,000
TOTAL OTHER COMPREHENSIVE INCOME (LOSS)		1,347,000	(1,378,000)	3,487,000	(6,321,000)
BALANCE		1,382,366,000	1,211,825,000	1,382,366,000	1,211,825,000
Unrealized gain (loss) on available-for-sale securities [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
BALANCE				(7,887,000)	(142,000)
Other comprehensive gain (loss) before reclassification				2,706,000	(7,231,000)
Reclassification to net income	[1]			0	0
TOTAL OTHER COMPREHENSIVE INCOME (LOSS)				2,706,000	(7,231,000)
BALANCE		(5,181,000)	(7,373,000)	(5,181,000)	(7,373,000)
Net unrealized gain (loss) on retirement plan [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
BALANCE	[2]			(10,011,000)	(18,019,000)
Other comprehensive gain (loss) before reclassification	[2]			0	0
Reclassification to net income	[1],[2]			759,000	1,511,000
TOTAL OTHER COMPREHENSIVE INCOME (LOSS)	[2]			759,000	1,511,000
BALANCE	[2]	(9,252,000)	(16,508,000)	(9,252,000)	(16,508,000)
Change in cumulative foreign currency translation adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
BALANCE				(554,000)	(74,000)
Other comprehensive gain (loss) before reclassification				22,000	(601,000)
Reclassification to net income	[1]			0	0
TOTAL OTHER COMPREHENSIVE INCOME (LOSS)				22,000	(601,000)
BALANCE		(532,000)	(675,000)	(532,000)	(675,000)
Accumulated Other Comprehensive Loss [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
BALANCE		(16,312,000)	(23,178,000)	(18,452,000)	(18,235,000)
Other comprehensive gain (loss) before reclassification				2,728,000	(7,832,000)
Reclassification to net income	[1]			759,000	1,511,000
TOTAL OTHER COMPREHENSIVE INCOME (LOSS)		1,347,000	(1,378,000)	3,487,000	(6,321,000)
BALANCE		$ (14,965,000)	$ (24,556,000)	$ (14,965,000)	$ (24,556,000)

[1] The Company reclassified amortization of prior service cost and actuarial loss for its retirement plan from accumulated other comprehensive loss to net income of $759,000 and $1.5 million for the nine months ended September 30, 2023 and 2022, respectively.

[2] Refer to Note 17: Retirement Plan Benefit Liability.