4. Property, Plant and Equipment, net (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Property Plant And Equipment Net Details
Leasehold improvements	$ 370us-gaap_LeaseholdImprovementsGross	$ 322us-gaap_LeaseholdImprovementsGross
Machinery and equipment	6,214us-gaap_MachineryAndEquipmentGross	5,576us-gaap_MachineryAndEquipmentGross
Less accumulated depreciation and amortization	(5,302)	(4,853)
Property, plant and equipment, net	$ 1,282us-gaap_PropertyPlantAndEquipmentNet	$ 1,045us-gaap_PropertyPlantAndEquipmentNet

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Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount before accumulated depreciation of additions or improvements to assets held under a lease arrangement.

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Amount before accumulated depreciation of tangible personal property used to produce goods and services, including, but is not limited to, tools, dies and molds, computer and office equipment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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