SIGNIFICANT ACCOUNTING POLICIES - Property (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Property, plant and equipment:
Depreciation expense			$ 18,669	$ 18,991	$ 19,627
Carrying value of long-lived assets:
Impairment charges of long-lived assets			$ 1,126	$ 2,371
Buildings | Minimum
Property, plant and equipment:
Useful lives			20 years
Buildings | Maximum
Property, plant and equipment:
Useful lives			35 years
Machinery and equipment | Minimum
Property, plant and equipment:
Useful lives			5 years
Machinery and equipment | Maximum
Property, plant and equipment:
Useful lives			20 years
Selling, Marketing, and Administrative Expense
Carrying value of long-lived assets:
Impairment charges of long-lived assets	$ 1,126	$ 2,371