BUSINESS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Property, Plant and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Property, plant and equipment
Property, plant and equipment, gross	$ 104,034	$ 90,361
Less accumulated depreciation	(51,026)	(42,326)
Property, plant and equipment, net	53,008	48,035
Depreciation expense	9,139	7,921	$ 7,055
Non-cash capital expenditures	376	598
Land
Property, plant and equipment
Property, plant and equipment, gross	977	981
Building and improvements
Property, plant and equipment
Property, plant and equipment, gross	$ 13,366	13,054
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	$ 73,894	60,755
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	$ 15,797	$ 15,571
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