ACCUMULATED OTHER COMPREHENSIVE INCOME/(LOSS) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax
Balance	$ 1,070,134
Other comprehensive income/(loss), net of tax	10,368	$ (2,968)	$ (23,944)
Balance	1,209,148	1,070,134
Foreign Currency Translation Adjustments
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax
Balance	(191,300)	(179,600)	(152,200)
Other comprehensive income/(loss) before reclassifications	12,000	(11,700)	(27,400)
Amounts reclassified from accumulated other comprehensive income/(loss)	0	0	0
Other comprehensive income/(loss), net of tax	12,000	(11,700)	(27,400)
Balance	(179,300)	(191,300)	(179,600)
Pension and Post-Retirement Plan Benefit Adjustments
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax
Balance	(40,100)	(49,000)	(52,600)
Other comprehensive income/(loss) before reclassifications	(3,300)	4,900	0
Amounts reclassified from accumulated other comprehensive income/(loss)	1,600	4,000	3,600
Other comprehensive income/(loss), net of tax	(1,700)	8,900	3,600
Balance	(41,800)	(40,100)	(49,000)
Other Comprehensive (Income) Loss, Defined Benefit Plan, before Reclassification Adjustment, Tax	(1,100)	1,800
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, Tax	500	1,800	1,500
AOCI Including Portion Attributable to Noncontrolling Interest
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax
Balance	(231,400)	(228,600)	(204,800)
Other comprehensive income/(loss) before reclassifications	8,700	(6,800)	(27,400)
Amounts reclassified from accumulated other comprehensive income/(loss)	1,600	4,000	3,600
Other comprehensive income/(loss), net of tax	10,300	(2,800)	(23,800)
Balance	$ (221,100)	$ (231,400)	$ (228,600)