SEGMENT INFORMATION - Business Segment Net Sales (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Segment information [Abstract]
Net sales	$ 185,656	$ 174,436
Other and Unallocated
Segment information [Abstract]
Net sales	1,984	2,291
Human Nutrition & Health | Operating Segments
Segment information [Abstract]
Net sales	104,516	95,508
Animal Nutrition & Health | Operating Segments
Segment information [Abstract]
Net sales	51,148	48,641
Specialty Products | Operating Segments
Segment information [Abstract]
Net sales	$ 28,008	$ 27,996