COMPREHENSIVE INCOME - Reclassification out of Accumulated other Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Loss on sale of business	$ (108)	$ (3,601)	$ (108)	$ (3,601)
Other – net	(2,586)	43	(2,792)	463
Benefit plans, net	7,450	2,471	14,986	5,501
Net income	(18,133)	(28,335)	(51,668)	(78,201)
Reclassification out of Accumulated Other Comprehensive Income | Release of currency translation gain with the sale of equity method investment and the sale of business
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Loss on sale of business	0	(3,176)	0	(3,176)
Reclassification out of Accumulated Other Comprehensive Income | Derivative financial instruments
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other – net	0	22	0	(202)
Net income	0	(3,154)	0	(3,378)
Reclassification out of Accumulated Other Comprehensive Income | Amortization of prior service cost on benefit obligations
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Benefit plans, net	246	514	492	870
Net income	$ 246	$ 514	$ 492	$ 870