Property, plant and equipment (Tables)

12 Months Ended

Dec. 31, 2016

Property, Plant and Equipment [Abstract]

Property, Plant and Equipment

Elements of property, plant and equipment are as follows:

December 31,	2016		2015		Estimated Lives
(in thousands)
Property, plant and equipment
- Land	$	535	$	535
- Buildings		830		830	39 years
- Building improvements		873		810	39 years
- Equipment		13,423		13,206	3-7 years
- Equipment under capital lease		248		234	5-7 years
- Vehicles		1,360		1,311	5 years
- Lab and computer equipment, software		2,652		2,499	3-5 years
- Furniture & fixtures		289		276	7-8 years
- Leasehold improvements		119		110	3 years
- Equipment under construction		1,654		491
Subtotal		21,983		20,302
Accumulated depreciation		14,451		12,766
Total	$	7,532	$	7,536