ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) - Components of Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	$ 743,667	$ 691,618
Other comprehensive income/(loss)	(2,905)	(1,084)
Ending balance	766,271	710,509
Total
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(5,564)	(3,602)
Other comprehensive income/(loss)	(2,905)	(1,084)
Ending balance	(8,469)	$ (4,686)
Foreign currency translation adjustment
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(5,176)
Other comprehensive income/(loss)	781
Ending balance	(4,395)
Cash flow hedges
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(1,399)
Other comprehensive income/(loss)	(3,107)
Ending balance	(4,506)
Postretirement benefit plan
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	1,011
Other comprehensive income/(loss)	(579)
Ending balance	$ 432