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DEBT - SCHEDULE OF DEBT (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Aug. 27, 2009
Debt Instrument [Line Items]
Long-term debt	$ 1,233,100
Total debt	1,233,100	$ 1,362,271
Debt Issuance Costs, Net	(9,575)	(13,711)
Less current and short-term portion	56,214	35,299
Total long-term debt	1,167,311	1,313,261
Secured Debt [Member]
Debt Instrument [Line Items]
Long-term debt	24,594	84,237
Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	500,000
Long-term debt	500,000	500,000
Senior Notes due 2024 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	350,000
Long-term debt	$ 350,000	350,000
Accounts receivable securitization facility
Debt Instrument [Line Items]
Long-term Debt, Percentage Bearing Variable Interest, Percentage Rate	1.95%
Long-term debt	$ 275,000	380,000
Revolving credit facility
Debt Instrument [Line Items]
Long-term Debt, Percentage Bearing Variable Interest, Percentage Rate	3.46%
Long-term debt	$ 51,598	12,000
Foreign Line of Credit [Member]
Debt Instrument [Line Items]
Long-term debt	$ 30,785	34,075
Convertible Debt
Debt Instrument [Line Items]
Debt Instrument, Face Amount			$ 345,000
Debt Instrument, Interest Rate, Effective Percentage	13.875%
Capital leases
Debt Instrument [Line Items]
Long-term debt	$ 1,123	$ 1,959
United States \| Secured Debt [Member]
Debt Instrument [Line Items]
Long-term Debt, Percentage Bearing Variable Interest, Percentage Rate	7.50%
Debt Instrument, Face Amount	$ 700,000
Debt Instrument, Interest Rate, Effective Percentage	1.00%