SEGMENT INFORMATION - Capital Expenditures (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Segment Reporting Information [Line Items]
Capital expenditures	$ 19,170	$ 27,526	$ 23,034
Human Nutrition & Health | Operating Segments
Segment Reporting Information [Line Items]
Capital expenditures	8,881	20,580	14,470
Animal Nutrition & Health | Operating Segments
Segment Reporting Information [Line Items]
Capital expenditures	6,021	4,424	6,577
Specialty Products | Operating Segments
Segment Reporting Information [Line Items]
Capital expenditures	2,356	1,306	1,286
Industrial Products | Operating Segments
Segment Reporting Information [Line Items]
Capital expenditures	$ 1,912	$ 1,216	$ 701