SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Property, Plant, and Equipment (Details 1) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 137,966	$ 142,892
Less accumulated depreciation	(55,116)	(65,264)
Property, plant and equipment, net	82,850	77,628
Land and improvements
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	11,807	11,333
Buildings and improvements
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	68,717	66,826
Machinery and equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	43,961	44,161
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	7,786	10,227
Software costs
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 5,695	$ 10,345