COMPONENTS OF THE COMPANY'S CONDENSED CONSOLIDATED BALANCE SHEETS - Changes in Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance			$ 749,772
Net-current period other comprehensive income (loss)	$ 896	$ (630)	1,736	$ (1,727)
Ending balance	703,788	730,742	703,788	730,742
Unrealized Gains and Losses on Marketable Securities
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	1,144	(432)	693	256
Other comprehensive income (loss) before reclassifications	238	(317)	689	(1,005)
Amounts reclassified from accumulated other comprehensive income (loss)	0	0	0	0
Net-current period other comprehensive income (loss)	238	(317)	689	(1,005)
Ending balance	1,382	(749)	1,382	(749)
Defined Benefit Pension Items
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	98	1,542	99	1,585
Other comprehensive income (loss) before reclassifications	0	0	0	0
Amounts reclassified from accumulated other comprehensive income (loss)	1	(42)	0	(85)
Net-current period other comprehensive income (loss)	1	(42)	0	(85)
Ending balance	99	1,500	99	1,500
Foreign Currency Items
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(3,425)	(3,669)	(3,815)	(3,303)
Other comprehensive income (loss) before reclassifications	657	(271)	1,047	(637)
Amounts reclassified from accumulated other comprehensive income (loss)	0	0	0	0
Net-current period other comprehensive income (loss)	657	(271)	1,047	(637)
Ending balance	(2,768)	(3,940)	(2,768)	(3,940)
Accumulated Other Comprehensive Income (Loss)
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(2,183)	(2,559)	(3,023)	(1,462)
Other comprehensive income (loss) before reclassifications	895	(588)	1,736	(1,642)
Amounts reclassified from accumulated other comprehensive income (loss)	1	(42)	0	(85)
Net-current period other comprehensive income (loss)	896	(630)	1,736	(1,727)
Ending balance	$ (1,287)	$ (3,189)	$ (1,287)	$ (3,189)