ACCUMULATED OTHER COMPREHENSIVE INCOME/(LOSS) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax
Equity, beginning balance	$ 1,070,134
Net other comprehensive income/(loss)	6,911	$ 9,524
Equity, ending balance	1,094,968
Income tax expense related to items of other comprehensive income/(loss)	138	260
Foreign Currency Translation Adjustments
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax
Equity, beginning balance	(191,300)	(179,600)
Other comprehensive income/(loss) before reclassifications	6,500	8,700
Amounts reclassified from accumulated other comprehensive income/(loss) (1)	0	0
Net other comprehensive income/(loss)	6,500	8,700
Equity, ending balance	(184,800)	(170,900)
Pension and Post-Retirement Plan Benefit Adjustments
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax
Equity, beginning balance	(40,100)	(49,000)
Other comprehensive income/(loss) before reclassifications	0	0
Amounts reclassified from accumulated other comprehensive income/(loss) (1)	300	900
Net other comprehensive income/(loss)	300	900
Equity, ending balance	(39,800)	(48,100)
AOCI Including Portion Attributable to Noncontrolling Interest
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax
Equity, beginning balance	(231,400)	(228,600)
Other comprehensive income/(loss) before reclassifications	6,500	8,700
Amounts reclassified from accumulated other comprehensive income/(loss) (1)	300	900
Net other comprehensive income/(loss)	6,800	9,600
Equity, ending balance	$ (224,600)	$ (219,000)