BUSINESS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Property, Plant and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Property, plant and equipment
Property, plant and equipment, gross	$ 73,685	$ 65,208
Less accumulated depreciation	(35,282)	(27,734)
Property, plant and equipment, net	38,403	37,474
Depreciation expense	7,055	6,545	$ 4,822
Land
Property, plant and equipment
Property, plant and equipment, gross	993	962
Building and improvements
Property, plant and equipment
Property, plant and equipment, gross	$ 10,678	9,911
Building and improvements | Minimum
Property, plant and equipment
Useful lives	5 years
Building and improvements | Maximum
Property, plant and equipment
Useful lives	39 years
Machinery, equipment, tools and dies
Property, plant and equipment
Property, plant and equipment, gross	$ 49,083	44,247
Machinery, equipment, tools and dies | Minimum
Property, plant and equipment
Useful lives	3 years
Machinery, equipment, tools and dies | Maximum
Property, plant and equipment
Useful lives	15 years
Furniture, fixtures and other
Property, plant and equipment
Property, plant and equipment, gross	$ 12,931	$ 10,088
Furniture, fixtures and other | Minimum
Property, plant and equipment
Useful lives	3 years
Furniture, fixtures and other | Maximum
Property, plant and equipment
Useful lives	10 years